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Selectables, Tables, FROM objects
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<h3><a href="#">
Selectables, Tables, FROM objects
</a></h3>
<ul>
<li><a class="reference internal" href="#">Selectables, Tables, FROM objects</a></li>
</ul>
</div>
</div>
<div id="docs-body" class="withsidebar" >
<div class="section" id="selectables-tables-from-objects">
<h1>Selectables, Tables, FROM objects<a class="headerlink" href="#selectables-tables-from-objects" title="Permalink to this headline">¶</a></h1>
<p>The term “selectable” refers to any object that rows can be selected from;
in SQLAlchemy, these objects descend from <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> and their
distinguishing feature is their <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.c" title="sqlalchemy.sql.expression.FromClause.c"><tt class="xref py py-attr docutils literal"><span class="pre">FromClause.c</span></tt></a> attribute, which is
a namespace of all the columns contained within the FROM clause (these
elements are themselves <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> subclasses).</p>
<span class="target" id="module-sqlalchemy.sql.expression"></span><dl class="function">
<dt id="sqlalchemy.sql.expression.alias">
<tt class="descclassname">sqlalchemy.sql.expression.</tt><tt class="descname">alias</tt><big>(</big><em>selectable</em>, <em>name=None</em>, <em>flat=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.alias" title="Permalink to this definition">¶</a></dt>
<dd><p>Return an <a class="reference internal" href="#sqlalchemy.sql.expression.Alias" title="sqlalchemy.sql.expression.Alias"><tt class="xref py py-class docutils literal"><span class="pre">Alias</span></tt></a> object.</p>
<p>An <a class="reference internal" href="#sqlalchemy.sql.expression.Alias" title="sqlalchemy.sql.expression.Alias"><tt class="xref py py-class docutils literal"><span class="pre">Alias</span></tt></a> represents any <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>
with an alternate name assigned within SQL, typically using the <tt class="docutils literal"><span class="pre">AS</span></tt>
clause when generated, e.g. <tt class="docutils literal"><span class="pre">SELECT</span> <span class="pre">*</span> <span class="pre">FROM</span> <span class="pre">table</span> <span class="pre">AS</span> <span class="pre">aliasname</span></tt>.</p>
<p>Similar functionality is available via the
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.alias" title="sqlalchemy.sql.expression.FromClause.alias"><tt class="xref py py-meth docutils literal"><span class="pre">alias()</span></tt></a> method
available on all <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> subclasses.</p>
<p>When an <a class="reference internal" href="#sqlalchemy.sql.expression.Alias" title="sqlalchemy.sql.expression.Alias"><tt class="xref py py-class docutils literal"><span class="pre">Alias</span></tt></a> is created from a <a class="reference internal" href="metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a> object,
this has the effect of the table being rendered
as <tt class="docutils literal"><span class="pre">tablename</span> <span class="pre">AS</span> <span class="pre">aliasname</span></tt> in a SELECT statement.</p>
<p>For <a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a> objects, the effect is that of creating a named
subquery, i.e. <tt class="docutils literal"><span class="pre">(select</span> <span class="pre">...)</span> <span class="pre">AS</span> <span class="pre">aliasname</span></tt>.</p>
<p>The <tt class="docutils literal"><span class="pre">name</span></tt> parameter is optional, and provides the name
to use in the rendered SQL. If blank, an “anonymous” name
will be deterministically generated at compile time.
Deterministic means the name is guaranteed to be unique against
other constructs used in the same statement, and will also be the
same name for each successive compilation of the same statement
object.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.alias.params.selectable"></span><strong>selectable</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.alias.params.selectable">¶</a> – any <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> subclass,
such as a table, select statement, etc.</li>
<li><span class="target" id="sqlalchemy.sql.expression.alias.params.name"></span><strong>name</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.alias.params.name">¶</a> – string name to be assigned as the alias.
If <tt class="docutils literal"><span class="pre">None</span></tt>, a name will be deterministically generated
at compile time.</li>
<li><span class="target" id="sqlalchemy.sql.expression.alias.params.flat"></span><strong>flat</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.alias.params.flat">¶</a> – <p>Will be passed through to if the given selectable
is an instance of <a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> - see <a class="reference internal" href="#sqlalchemy.sql.expression.Join.alias" title="sqlalchemy.sql.expression.Join.alias"><tt class="xref py py-meth docutils literal"><span class="pre">Join.alias()</span></tt></a>
for details.</p>
<div class="versionadded">
<p><span>New in version 0.9.0.</span></p>
</div>
</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
<dl class="function">
<dt id="sqlalchemy.sql.expression.except_">
<tt class="descclassname">sqlalchemy.sql.expression.</tt><tt class="descname">except_</tt><big>(</big><em>*selects</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.except_" title="Permalink to this definition">¶</a></dt>
<dd><p>Return an <tt class="docutils literal"><span class="pre">EXCEPT</span></tt> of multiple selectables.</p>
<p>The returned object is an instance of
<a class="reference internal" href="#sqlalchemy.sql.expression.CompoundSelect" title="sqlalchemy.sql.expression.CompoundSelect"><tt class="xref py py-class docutils literal"><span class="pre">CompoundSelect</span></tt></a>.</p>
<dl class="docutils">
<dt>*selects</dt>
<dd>a list of <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> instances.</dd>
<dt>**kwargs</dt>
<dd>available keyword arguments are the same as those of
<a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a>.</dd>
</dl>
</dd></dl>
<dl class="function">
<dt id="sqlalchemy.sql.expression.except_all">
<tt class="descclassname">sqlalchemy.sql.expression.</tt><tt class="descname">except_all</tt><big>(</big><em>*selects</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.except_all" title="Permalink to this definition">¶</a></dt>
<dd><p>Return an <tt class="docutils literal"><span class="pre">EXCEPT</span> <span class="pre">ALL</span></tt> of multiple selectables.</p>
<p>The returned object is an instance of
<a class="reference internal" href="#sqlalchemy.sql.expression.CompoundSelect" title="sqlalchemy.sql.expression.CompoundSelect"><tt class="xref py py-class docutils literal"><span class="pre">CompoundSelect</span></tt></a>.</p>
<dl class="docutils">
<dt>*selects</dt>
<dd>a list of <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> instances.</dd>
<dt>**kwargs</dt>
<dd>available keyword arguments are the same as those of
<a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a>.</dd>
</dl>
</dd></dl>
<dl class="function">
<dt id="sqlalchemy.sql.expression.exists">
<tt class="descclassname">sqlalchemy.sql.expression.</tt><tt class="descname">exists</tt><big>(</big><em>*args</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.exists" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct a new <tt class="xref py py-class docutils literal"><span class="pre">Exists</span></tt> against an existing
<a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> object.</p>
<p>Calling styles are of the following forms:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="c"># use on an existing select()</span>
<span class="n">s</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">col1</span><span class="p">])</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="n">table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">col2</span><span class="o">==</span><span class="mi">5</span><span class="p">)</span>
<span class="n">s</span> <span class="o">=</span> <span class="n">exists</span><span class="p">(</span><span class="n">s</span><span class="p">)</span>
<span class="c"># construct a select() at once</span>
<span class="n">exists</span><span class="p">([</span><span class="s">'*'</span><span class="p">],</span> <span class="o">**</span><span class="n">select_arguments</span><span class="p">)</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="n">criterion</span><span class="p">)</span>
<span class="c"># columns argument is optional, generates "EXISTS (SELECT *)"</span>
<span class="c"># by default.</span>
<span class="n">exists</span><span class="p">()</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="n">table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">col2</span><span class="o">==</span><span class="mi">5</span><span class="p">)</span></pre></div>
</div>
</dd></dl>
<dl class="function">
<dt id="sqlalchemy.sql.expression.intersect">
<tt class="descclassname">sqlalchemy.sql.expression.</tt><tt class="descname">intersect</tt><big>(</big><em>*selects</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.intersect" title="Permalink to this definition">¶</a></dt>
<dd><p>Return an <tt class="docutils literal"><span class="pre">INTERSECT</span></tt> of multiple selectables.</p>
<p>The returned object is an instance of
<a class="reference internal" href="#sqlalchemy.sql.expression.CompoundSelect" title="sqlalchemy.sql.expression.CompoundSelect"><tt class="xref py py-class docutils literal"><span class="pre">CompoundSelect</span></tt></a>.</p>
<dl class="docutils">
<dt>*selects</dt>
<dd>a list of <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> instances.</dd>
<dt>**kwargs</dt>
<dd>available keyword arguments are the same as those of
<a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a>.</dd>
</dl>
</dd></dl>
<dl class="function">
<dt id="sqlalchemy.sql.expression.intersect_all">
<tt class="descclassname">sqlalchemy.sql.expression.</tt><tt class="descname">intersect_all</tt><big>(</big><em>*selects</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.intersect_all" title="Permalink to this definition">¶</a></dt>
<dd><p>Return an <tt class="docutils literal"><span class="pre">INTERSECT</span> <span class="pre">ALL</span></tt> of multiple selectables.</p>
<p>The returned object is an instance of
<a class="reference internal" href="#sqlalchemy.sql.expression.CompoundSelect" title="sqlalchemy.sql.expression.CompoundSelect"><tt class="xref py py-class docutils literal"><span class="pre">CompoundSelect</span></tt></a>.</p>
<dl class="docutils">
<dt>*selects</dt>
<dd>a list of <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> instances.</dd>
<dt>**kwargs</dt>
<dd>available keyword arguments are the same as those of
<a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a>.</dd>
</dl>
</dd></dl>
<dl class="function">
<dt id="sqlalchemy.sql.expression.join">
<tt class="descclassname">sqlalchemy.sql.expression.</tt><tt class="descname">join</tt><big>(</big><em>left</em>, <em>right</em>, <em>onclause=None</em>, <em>isouter=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.join" title="Permalink to this definition">¶</a></dt>
<dd><p>Produce a <a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> object, given two <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>
expressions.</p>
<p>E.g.:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">j</span> <span class="o">=</span> <span class="n">join</span><span class="p">(</span><span class="n">user_table</span><span class="p">,</span> <span class="n">address_table</span><span class="p">,</span>
<span class="n">user_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span> <span class="o">==</span> <span class="n">address_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">user_id</span><span class="p">)</span>
<span class="n">stmt</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">user_table</span><span class="p">])</span><span class="o">.</span><span class="n">select_from</span><span class="p">(</span><span class="n">j</span><span class="p">)</span></pre></div>
</div>
<p>would emit SQL along the lines of:</p>
<div class="highlight-python"><pre>SELECT user.id, user.name FROM user
JOIN address ON user.id = address.user_id</pre>
</div>
<p>Similar functionality is available given any
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> object (e.g. such as a <a class="reference internal" href="metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a>) using
the <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a> method.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.join.params.left"></span><strong>left</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.join.params.left">¶</a> – The left side of the join.</li>
<li><span class="target" id="sqlalchemy.sql.expression.join.params.right"></span><strong>right</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.join.params.right">¶</a> – the right side of the join; this is any
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> object such as a <a class="reference internal" href="metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a> object, and
may also be a selectable-compatible object such as an ORM-mapped
class.</li>
<li><span class="target" id="sqlalchemy.sql.expression.join.params.onclause"></span><strong>onclause</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.join.params.onclause">¶</a> – a SQL expression representing the ON clause of the
join. If left at <tt class="docutils literal"><span class="pre">None</span></tt>, <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a> will attempt to
join the two tables based on a foreign key relationship.</li>
<li><span class="target" id="sqlalchemy.sql.expression.join.params.isouter"></span><strong>isouter</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.join.params.isouter">¶</a> – if True, render a LEFT OUTER JOIN, instead of JOIN.</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p><a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a> - method form, based on a given left side</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> - the type of object produced</p>
</div>
</dd></dl>
<dl class="function">
<dt id="sqlalchemy.sql.expression.outerjoin">
<tt class="descclassname">sqlalchemy.sql.expression.</tt><tt class="descname">outerjoin</tt><big>(</big><em>left</em>, <em>right</em>, <em>onclause=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.outerjoin" title="Permalink to this definition">¶</a></dt>
<dd><p>Return an <tt class="docutils literal"><span class="pre">OUTER</span> <span class="pre">JOIN</span></tt> clause element.</p>
<p>The returned object is an instance of <a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a>.</p>
<p>Similar functionality is also available via the
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.outerjoin" title="sqlalchemy.sql.expression.FromClause.outerjoin"><tt class="xref py py-meth docutils literal"><span class="pre">outerjoin()</span></tt></a> method on any
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.outerjoin.params.left"></span><strong>left</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.outerjoin.params.left">¶</a> – The left side of the join.</li>
<li><span class="target" id="sqlalchemy.sql.expression.outerjoin.params.right"></span><strong>right</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.outerjoin.params.right">¶</a> – The right side of the join.</li>
<li><span class="target" id="sqlalchemy.sql.expression.outerjoin.params.onclause"></span><strong>onclause</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.outerjoin.params.onclause">¶</a> – Optional criterion for the <tt class="docutils literal"><span class="pre">ON</span></tt> clause, is
derived from foreign key relationships established between
left and right otherwise.</li>
</ul>
</td>
</tr>
</tbody>
</table>
<p>To chain joins together, use the <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a> or
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.outerjoin" title="sqlalchemy.sql.expression.FromClause.outerjoin"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.outerjoin()</span></tt></a> methods on the resulting
<a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> object.</p>
</dd></dl>
<dl class="function">
<dt id="sqlalchemy.sql.expression.select">
<tt class="descclassname">sqlalchemy.sql.expression.</tt><tt class="descname">select</tt><big>(</big><em>columns=None</em>, <em>whereclause=None</em>, <em>from_obj=None</em>, <em>distinct=False</em>, <em>having=None</em>, <em>correlate=True</em>, <em>prefixes=None</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.select" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct a new <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a>.</p>
<p>Similar functionality is also available via the
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.select" title="sqlalchemy.sql.expression.FromClause.select"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.select()</span></tt></a> method on any <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<p>All arguments which accept <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a> arguments also
accept string arguments, which will be converted as appropriate into
either <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.text" title="sqlalchemy.sql.expression.text"><tt class="xref py py-func docutils literal"><span class="pre">text()</span></tt></a> or <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.literal_column" title="sqlalchemy.sql.expression.literal_column"><tt class="xref py py-func docutils literal"><span class="pre">literal_column()</span></tt></a> constructs.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="tutorial.html#coretutorial-selecting"><em>Selecting</em></a> - Core Tutorial description of
<a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a>.</p>
</div>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.select.params.columns"></span><strong>columns</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.select.params.columns">¶</a> – <p>A list of <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> or <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>
objects which will form the columns clause of the resulting
statement. For those objects that are instances of
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> (typically <a class="reference internal" href="metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a> or <a class="reference internal" href="#sqlalchemy.sql.expression.Alias" title="sqlalchemy.sql.expression.Alias"><tt class="xref py py-class docutils literal"><span class="pre">Alias</span></tt></a>
objects), the <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.c" title="sqlalchemy.sql.expression.FromClause.c"><tt class="xref py py-attr docutils literal"><span class="pre">FromClause.c</span></tt></a> collection is extracted
to form a collection of <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> objects.</p>
<p>This parameter will also accept <a class="reference internal" href="types.html#sqlalchemy.types.Text" title="sqlalchemy.types.Text"><tt class="xref py py-class docutils literal"><span class="pre">Text</span></tt></a> constructs as
given, as well as ORM-mapped classes.</p>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">The <a class="reference internal" href="#sqlalchemy.sql.expression.select.params.columns" title="sqlalchemy.sql.expression.select"><tt class="xref py py-paramref docutils literal"><span class="pre">select.columns</span></tt></a> parameter is not available
in the method form of <a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a>, e.g.
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.select" title="sqlalchemy.sql.expression.FromClause.select"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.select()</span></tt></a>.</p>
</div>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p><a class="reference internal" href="#sqlalchemy.sql.expression.Select.column" title="sqlalchemy.sql.expression.Select.column"><tt class="xref py py-meth docutils literal"><span class="pre">Select.column()</span></tt></a></p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.Select.with_only_columns" title="sqlalchemy.sql.expression.Select.with_only_columns"><tt class="xref py py-meth docutils literal"><span class="pre">Select.with_only_columns()</span></tt></a></p>
</div>
</li>
<li><span class="target" id="sqlalchemy.sql.expression.select.params.whereclause"></span><strong>whereclause</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.select.params.whereclause">¶</a> – <p>A <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a> expression which will be used to form the
<tt class="docutils literal"><span class="pre">WHERE</span></tt> clause. It is typically preferable to add WHERE
criterion to an existing <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> using method chaining
with <a class="reference internal" href="#sqlalchemy.sql.expression.Select.where" title="sqlalchemy.sql.expression.Select.where"><tt class="xref py py-meth docutils literal"><span class="pre">Select.where()</span></tt></a>.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.Select.where" title="sqlalchemy.sql.expression.Select.where"><tt class="xref py py-meth docutils literal"><span class="pre">Select.where()</span></tt></a></p>
</div>
</li>
<li><span class="target" id="sqlalchemy.sql.expression.select.params.from_obj"></span><strong>from_obj</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.select.params.from_obj">¶</a> – <p>A list of <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a> objects which will be added to the
<tt class="docutils literal"><span class="pre">FROM</span></tt> clause of the resulting statement. This is equivalent
to calling <a class="reference internal" href="#sqlalchemy.sql.expression.Select.select_from" title="sqlalchemy.sql.expression.Select.select_from"><tt class="xref py py-meth docutils literal"><span class="pre">Select.select_from()</span></tt></a> using method chaining on
an existing <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> object.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.Select.select_from" title="sqlalchemy.sql.expression.Select.select_from"><tt class="xref py py-meth docutils literal"><span class="pre">Select.select_from()</span></tt></a> - full description of explicit
FROM clause specification.</p>
</div>
</li>
<li><span class="target" id="sqlalchemy.sql.expression.select.params.autocommit"></span><strong>autocommit</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.select.params.autocommit">¶</a> – <p>Deprecated. Use <tt class="docutils literal"><span class="pre">.execution_options(autocommit=<True|False>)</span></tt>
to set the autocommit option.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.Executable.execution_options" title="sqlalchemy.sql.expression.Executable.execution_options"><tt class="xref py py-meth docutils literal"><span class="pre">Executable.execution_options()</span></tt></a></p>
</div>
</li>
<li><span class="target" id="sqlalchemy.sql.expression.select.params.bind"></span><strong>bind=None</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.select.params.bind">¶</a> – an <a class="reference internal" href="connections.html#sqlalchemy.engine.Engine" title="sqlalchemy.engine.Engine"><tt class="xref py py-class docutils literal"><span class="pre">Engine</span></tt></a> or <a class="reference internal" href="connections.html#sqlalchemy.engine.Connection" title="sqlalchemy.engine.Connection"><tt class="xref py py-class docutils literal"><span class="pre">Connection</span></tt></a> instance
to which the
resulting <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> object will be bound. The
<a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> object will otherwise automatically bind to
whatever <tt class="xref py py-class docutils literal"><span class="pre">Connectable</span></tt> instances can be located within
its contained <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a> members.</li>
<li><span class="target" id="sqlalchemy.sql.expression.select.params.correlate"></span><strong>correlate=True</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.select.params.correlate">¶</a> – <p>indicates that this <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> object should have its
contained <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> elements “correlated” to an enclosing
<a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> object. It is typically preferable to specify
correlations on an existing <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> construct using
<a class="reference internal" href="#sqlalchemy.sql.expression.Select.correlate" title="sqlalchemy.sql.expression.Select.correlate"><tt class="xref py py-meth docutils literal"><span class="pre">Select.correlate()</span></tt></a>.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.Select.correlate" title="sqlalchemy.sql.expression.Select.correlate"><tt class="xref py py-meth docutils literal"><span class="pre">Select.correlate()</span></tt></a> - full description of correlation.</p>
</div>
</li>
<li><span class="target" id="sqlalchemy.sql.expression.select.params.distinct"></span><strong>distinct=False</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.select.params.distinct">¶</a> – <p>when <tt class="docutils literal"><span class="pre">True</span></tt>, applies a <tt class="docutils literal"><span class="pre">DISTINCT</span></tt> qualifier to the columns
clause of the resulting statement.</p>
<p>The boolean argument may also be a column expression or list
of column expressions - this is a special calling form which
is understood by the Postgresql dialect to render the
<tt class="docutils literal"><span class="pre">DISTINCT</span> <span class="pre">ON</span> <span class="pre">(<columns>)</span></tt> syntax.</p>
<p><tt class="docutils literal"><span class="pre">distinct</span></tt> is also available on an existing <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a>
object via the <a class="reference internal" href="#sqlalchemy.sql.expression.Select.distinct" title="sqlalchemy.sql.expression.Select.distinct"><tt class="xref py py-meth docutils literal"><span class="pre">distinct()</span></tt></a> method.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.Select.distinct" title="sqlalchemy.sql.expression.Select.distinct"><tt class="xref py py-meth docutils literal"><span class="pre">Select.distinct()</span></tt></a></p>
</div>
</li>
<li><span class="target" id="sqlalchemy.sql.expression.select.params.for_update"></span><strong>for_update=False</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.select.params.for_update">¶</a> – <blockquote>
<div>when <tt class="docutils literal"><span class="pre">True</span></tt>, applies <tt class="docutils literal"><span class="pre">FOR</span> <span class="pre">UPDATE</span></tt> to the end of the
resulting statement.<div class="deprecated">
<p><span>Deprecated since version 0.9.0: </span>- use
<a class="reference internal" href="#sqlalchemy.sql.expression.Select.with_for_update" title="sqlalchemy.sql.expression.Select.with_for_update"><tt class="xref py py-meth docutils literal"><span class="pre">Select.with_for_update()</span></tt></a> to specify the
structure of the <tt class="docutils literal"><span class="pre">FOR</span> <span class="pre">UPDATE</span></tt> clause.</p>
</div>
<p><tt class="docutils literal"><span class="pre">for_update</span></tt> accepts various string values interpreted by
specific backends, including:</p>
<ul>
<li><tt class="docutils literal"><span class="pre">"read"</span></tt> - on MySQL, translates to <tt class="docutils literal"><span class="pre">LOCK</span> <span class="pre">IN</span> <span class="pre">SHARE</span> <span class="pre">MODE</span></tt>;
on Postgresql, translates to <tt class="docutils literal"><span class="pre">FOR</span> <span class="pre">SHARE</span></tt>.</li>
<li><tt class="docutils literal"><span class="pre">"nowait"</span></tt> - on Postgresql and Oracle, translates to
<tt class="docutils literal"><span class="pre">FOR</span> <span class="pre">UPDATE</span> <span class="pre">NOWAIT</span></tt>.</li>
<li><tt class="docutils literal"><span class="pre">"read_nowait"</span></tt> - on Postgresql, translates to
<tt class="docutils literal"><span class="pre">FOR</span> <span class="pre">SHARE</span> <span class="pre">NOWAIT</span></tt>.</li>
</ul>
</div></blockquote>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.Select.with_for_update" title="sqlalchemy.sql.expression.Select.with_for_update"><tt class="xref py py-meth docutils literal"><span class="pre">Select.with_for_update()</span></tt></a> - improved API for
specifying the <tt class="docutils literal"><span class="pre">FOR</span> <span class="pre">UPDATE</span></tt> clause.</p>
</div>
</li>
<li><span class="target" id="sqlalchemy.sql.expression.select.params.group_by"></span><strong>group_by</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.select.params.group_by">¶</a> – <p>a list of <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a> objects which will comprise the
<tt class="docutils literal"><span class="pre">GROUP</span> <span class="pre">BY</span></tt> clause of the resulting select. This parameter
is typically specified more naturally using the
<a class="reference internal" href="#sqlalchemy.sql.expression.Select.group_by" title="sqlalchemy.sql.expression.Select.group_by"><tt class="xref py py-meth docutils literal"><span class="pre">Select.group_by()</span></tt></a> method on an existing <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a>.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.Select.group_by" title="sqlalchemy.sql.expression.Select.group_by"><tt class="xref py py-meth docutils literal"><span class="pre">Select.group_by()</span></tt></a></p>
</div>
</li>
<li><span class="target" id="sqlalchemy.sql.expression.select.params.having"></span><strong>having</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.select.params.having">¶</a> – <p>a <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a> that will comprise the <tt class="docutils literal"><span class="pre">HAVING</span></tt> clause
of the resulting select when <tt class="docutils literal"><span class="pre">GROUP</span> <span class="pre">BY</span></tt> is used. This parameter
is typically specified more naturally using the
<a class="reference internal" href="#sqlalchemy.sql.expression.Select.having" title="sqlalchemy.sql.expression.Select.having"><tt class="xref py py-meth docutils literal"><span class="pre">Select.having()</span></tt></a> method on an existing <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a>.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.Select.having" title="sqlalchemy.sql.expression.Select.having"><tt class="xref py py-meth docutils literal"><span class="pre">Select.having()</span></tt></a></p>
</div>
</li>
<li><span class="target" id="sqlalchemy.sql.expression.select.params.limit"></span><strong>limit=None</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.select.params.limit">¶</a> – <p>a numerical value which usually renders as a <tt class="docutils literal"><span class="pre">LIMIT</span></tt>
expression in the resulting select. Backends that don’t
support <tt class="docutils literal"><span class="pre">LIMIT</span></tt> will attempt to provide similar
functionality. This parameter is typically specified more naturally
using the <a class="reference internal" href="#sqlalchemy.sql.expression.Select.limit" title="sqlalchemy.sql.expression.Select.limit"><tt class="xref py py-meth docutils literal"><span class="pre">Select.limit()</span></tt></a> method on an existing
<a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a>.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.Select.limit" title="sqlalchemy.sql.expression.Select.limit"><tt class="xref py py-meth docutils literal"><span class="pre">Select.limit()</span></tt></a></p>
</div>
</li>
<li><span class="target" id="sqlalchemy.sql.expression.select.params.offset"></span><strong>offset=None</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.select.params.offset">¶</a> – <p>a numeric value which usually renders as an <tt class="docutils literal"><span class="pre">OFFSET</span></tt>
expression in the resulting select. Backends that don’t
support <tt class="docutils literal"><span class="pre">OFFSET</span></tt> will attempt to provide similar
functionality. This parameter is typically specified more naturally
using the <a class="reference internal" href="#sqlalchemy.sql.expression.Select.offset" title="sqlalchemy.sql.expression.Select.offset"><tt class="xref py py-meth docutils literal"><span class="pre">Select.offset()</span></tt></a> method on an existing
<a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a>.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.Select.offset" title="sqlalchemy.sql.expression.Select.offset"><tt class="xref py py-meth docutils literal"><span class="pre">Select.offset()</span></tt></a></p>
</div>
</li>
<li><span class="target" id="sqlalchemy.sql.expression.select.params.order_by"></span><strong>order_by</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.select.params.order_by">¶</a> – <p>a scalar or list of <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a> objects which will
comprise the <tt class="docutils literal"><span class="pre">ORDER</span> <span class="pre">BY</span></tt> clause of the resulting select.
This parameter is typically specified more naturally using the
<a class="reference internal" href="#sqlalchemy.sql.expression.Select.order_by" title="sqlalchemy.sql.expression.Select.order_by"><tt class="xref py py-meth docutils literal"><span class="pre">Select.order_by()</span></tt></a> method on an existing <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a>.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.Select.order_by" title="sqlalchemy.sql.expression.Select.order_by"><tt class="xref py py-meth docutils literal"><span class="pre">Select.order_by()</span></tt></a></p>
</div>
</li>
<li><span class="target" id="sqlalchemy.sql.expression.select.params.use_labels"></span><strong>use_labels=False</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.select.params.use_labels">¶</a> – <p>when <tt class="docutils literal"><span class="pre">True</span></tt>, the statement will be generated using labels
for each column in the columns clause, which qualify each
column with its parent table’s (or aliases) name so that name
conflicts between columns in different tables don’t occur.
The format of the label is <tablename>_<column>. The “c”
collection of the resulting <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> object will use these
names as well for targeting column members.</p>
<p>This parameter can also be specified on an existing
<a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> object using the <a class="reference internal" href="#sqlalchemy.sql.expression.Select.apply_labels" title="sqlalchemy.sql.expression.Select.apply_labels"><tt class="xref py py-meth docutils literal"><span class="pre">Select.apply_labels()</span></tt></a>
method.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.Select.apply_labels" title="sqlalchemy.sql.expression.Select.apply_labels"><tt class="xref py py-meth docutils literal"><span class="pre">Select.apply_labels()</span></tt></a></p>
</div>
</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
<dl class="function">
<dt id="sqlalchemy.sql.expression.subquery">
<tt class="descclassname">sqlalchemy.sql.expression.</tt><tt class="descname">subquery</tt><big>(</big><em>alias</em>, <em>*args</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.subquery" title="Permalink to this definition">¶</a></dt>
<dd><p>Return an <a class="reference internal" href="#sqlalchemy.sql.expression.Alias" title="sqlalchemy.sql.expression.Alias"><tt class="xref py py-class docutils literal"><span class="pre">Alias</span></tt></a> object derived
from a <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a>.</p>
<dl class="docutils">
<dt>name</dt>
<dd>alias name</dd>
</dl>
<p>*args, **kwargs</p>
<blockquote>
<div>all other arguments are delivered to the
<a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a> function.</div></blockquote>
</dd></dl>
<dl class="function">
<dt id="sqlalchemy.sql.expression.table">
<tt class="descclassname">sqlalchemy.sql.expression.</tt><tt class="descname">table</tt><big>(</big><em>name</em>, <em>*columns</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.table" title="Permalink to this definition">¶</a></dt>
<dd><p>Produce a new <a class="reference internal" href="#sqlalchemy.sql.expression.TableClause" title="sqlalchemy.sql.expression.TableClause"><tt class="xref py py-class docutils literal"><span class="pre">TableClause</span></tt></a>.</p>
<p>The object returned is an instance of <a class="reference internal" href="#sqlalchemy.sql.expression.TableClause" title="sqlalchemy.sql.expression.TableClause"><tt class="xref py py-class docutils literal"><span class="pre">TableClause</span></tt></a>, which
represents the “syntactical” portion of the schema-level
<a class="reference internal" href="metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a> object.
It may be used to construct lightweight table constructs.</p>
<p>Note that the <a class="reference internal" href="#sqlalchemy.sql.expression.table" title="sqlalchemy.sql.expression.table"><tt class="xref py py-func docutils literal"><span class="pre">expression.table()</span></tt></a> function is not part of
the <tt class="docutils literal"><span class="pre">sqlalchemy</span></tt> namespace. It must be imported from the
<tt class="docutils literal"><span class="pre">sql</span></tt> package:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy.sql</span> <span class="kn">import</span> <span class="n">table</span><span class="p">,</span> <span class="n">column</span></pre></div>
</div>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.table.params.name"></span><strong>name</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.table.params.name">¶</a> – Name of the table.</li>
<li><span class="target" id="sqlalchemy.sql.expression.table.params.columns"></span><strong>columns</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.table.params.columns">¶</a> – A collection of <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.column" title="sqlalchemy.sql.expression.column"><tt class="xref py py-func docutils literal"><span class="pre">expression.column()</span></tt></a> constructs.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
<dl class="function">
<dt id="sqlalchemy.sql.expression.union">
<tt class="descclassname">sqlalchemy.sql.expression.</tt><tt class="descname">union</tt><big>(</big><em>*selects</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.union" title="Permalink to this definition">¶</a></dt>
<dd><p>Return a <tt class="docutils literal"><span class="pre">UNION</span></tt> of multiple selectables.</p>
<p>The returned object is an instance of
<a class="reference internal" href="#sqlalchemy.sql.expression.CompoundSelect" title="sqlalchemy.sql.expression.CompoundSelect"><tt class="xref py py-class docutils literal"><span class="pre">CompoundSelect</span></tt></a>.</p>
<p>A similar <a class="reference internal" href="#sqlalchemy.sql.expression.union" title="sqlalchemy.sql.expression.union"><tt class="xref py py-func docutils literal"><span class="pre">union()</span></tt></a> method is available on all
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> subclasses.</p>
<dl class="docutils">
<dt>*selects</dt>
<dd>a list of <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> instances.</dd>
<dt>**kwargs</dt>
<dd>available keyword arguments are the same as those of
<a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a>.</dd>
</dl>
</dd></dl>
<dl class="function">
<dt id="sqlalchemy.sql.expression.union_all">
<tt class="descclassname">sqlalchemy.sql.expression.</tt><tt class="descname">union_all</tt><big>(</big><em>*selects</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.union_all" title="Permalink to this definition">¶</a></dt>
<dd><p>Return a <tt class="docutils literal"><span class="pre">UNION</span> <span class="pre">ALL</span></tt> of multiple selectables.</p>
<p>The returned object is an instance of
<a class="reference internal" href="#sqlalchemy.sql.expression.CompoundSelect" title="sqlalchemy.sql.expression.CompoundSelect"><tt class="xref py py-class docutils literal"><span class="pre">CompoundSelect</span></tt></a>.</p>
<p>A similar <a class="reference internal" href="#sqlalchemy.sql.expression.union_all" title="sqlalchemy.sql.expression.union_all"><tt class="xref py py-func docutils literal"><span class="pre">union_all()</span></tt></a> method is available on all
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> subclasses.</p>
<dl class="docutils">
<dt>*selects</dt>
<dd>a list of <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> instances.</dd>
<dt>**kwargs</dt>
<dd>available keyword arguments are the same as those of
<a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a>.</dd>
</dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.sql.expression.Alias">
<em class="property">class </em><tt class="descclassname">sqlalchemy.sql.expression.</tt><tt class="descname">Alias</tt><big>(</big><em>selectable</em>, <em>name=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Alias" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.sql.expression.FromClause</span></tt></a></p>
<p>Represents an table or selectable alias (AS).</p>
<p>Represents an alias, as typically applied to any table or
sub-select within a SQL statement using the <tt class="docutils literal"><span class="pre">AS</span></tt> keyword (or
without the keyword on certain databases such as Oracle).</p>
<p>This object is constructed from the <a class="reference internal" href="#sqlalchemy.sql.expression.alias" title="sqlalchemy.sql.expression.alias"><tt class="xref py py-func docutils literal"><span class="pre">alias()</span></tt></a> module
level function as well as the <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.alias" title="sqlalchemy.sql.expression.FromClause.alias"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.alias()</span></tt></a> method available
on all <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> subclasses.</p>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Alias.alias">
<tt class="descname">alias</tt><big>(</big><em>name=None</em>, <em>flat=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Alias.alias" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.alias" title="sqlalchemy.sql.expression.FromClause.alias"><tt class="xref py py-meth docutils literal"><span class="pre">alias()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>return an alias of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<p>This is shorthand for calling:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="n">alias</span>
<span class="n">a</span> <span class="o">=</span> <span class="n">alias</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">name</span><span class="o">=</span><span class="n">name</span><span class="p">)</span></pre></div>
</div>
<p>See <a class="reference internal" href="#sqlalchemy.sql.expression.alias" title="sqlalchemy.sql.expression.alias"><tt class="xref py py-func docutils literal"><span class="pre">alias()</span></tt></a> for details.</p>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.Alias.c">
<tt class="descname">c</tt><a class="headerlink" href="#sqlalchemy.sql.expression.Alias.c" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.c" title="sqlalchemy.sql.expression.FromClause.c"><tt class="xref py py-attr docutils literal"><span class="pre">c</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>An alias for the <a class="reference internal" href="#sqlalchemy.sql.expression.Alias.columns" title="sqlalchemy.sql.expression.Alias.columns"><tt class="xref py py-attr docutils literal"><span class="pre">columns</span></tt></a> attribute.</p>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.Alias.columns">
<tt class="descname">columns</tt><a class="headerlink" href="#sqlalchemy.sql.expression.Alias.columns" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.columns" title="sqlalchemy.sql.expression.FromClause.columns"><tt class="xref py py-attr docutils literal"><span class="pre">columns</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>A named-based collection of <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> objects
maintained by this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<p>The <a class="reference internal" href="#sqlalchemy.sql.expression.Alias.columns" title="sqlalchemy.sql.expression.Alias.columns"><tt class="xref py py-attr docutils literal"><span class="pre">columns</span></tt></a>, or <a class="reference internal" href="#sqlalchemy.sql.expression.Alias.c" title="sqlalchemy.sql.expression.Alias.c"><tt class="xref py py-attr docutils literal"><span class="pre">c</span></tt></a> collection, is the gateway
to the construction of SQL expressions using table-bound or
other selectable-bound columns:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">select</span><span class="p">([</span><span class="n">mytable</span><span class="p">])</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="n">mytable</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">somecolumn</span> <span class="o">==</span> <span class="mi">5</span><span class="p">)</span></pre></div>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Alias.compare">
<tt class="descname">compare</tt><big>(</big><em>other</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Alias.compare" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.compare" title="sqlalchemy.sql.expression.ClauseElement.compare"><tt class="xref py py-meth docutils literal"><span class="pre">compare()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Compare this ClauseElement to the given ClauseElement.</p>
<p>Subclasses should override the default behavior, which is a
straight identity comparison.</p>
<p>**kw are arguments consumed by subclass compare() methods and
may be used to modify the criteria for comparison.
(see <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a>)</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Alias.compile">
<tt class="descname">compile</tt><big>(</big><em>bind=None</em>, <em>dialect=None</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Alias.compile" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.compile" title="sqlalchemy.sql.expression.ClauseElement.compile"><tt class="xref py py-meth docutils literal"><span class="pre">compile()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Compile this SQL expression.</p>
<p>The return value is a <a class="reference internal" href="internals.html#sqlalchemy.engine.interfaces.Compiled" title="sqlalchemy.engine.interfaces.Compiled"><tt class="xref py py-class docutils literal"><span class="pre">Compiled</span></tt></a> object.
Calling <tt class="docutils literal"><span class="pre">str()</span></tt> or <tt class="docutils literal"><span class="pre">unicode()</span></tt> on the returned value will yield a
string representation of the result. The
<a class="reference internal" href="internals.html#sqlalchemy.engine.interfaces.Compiled" title="sqlalchemy.engine.interfaces.Compiled"><tt class="xref py py-class docutils literal"><span class="pre">Compiled</span></tt></a> object also can return a
dictionary of bind parameter names and values
using the <tt class="docutils literal"><span class="pre">params</span></tt> accessor.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.Alias.compile.params.bind"></span><strong>bind</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Alias.compile.params.bind">¶</a> – An <tt class="docutils literal"><span class="pre">Engine</span></tt> or <tt class="docutils literal"><span class="pre">Connection</span></tt> from which a
<tt class="docutils literal"><span class="pre">Compiled</span></tt> will be acquired. This argument takes precedence over
this <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a>‘s bound engine, if any.</li>
<li><span class="target" id="sqlalchemy.sql.expression.Alias.compile.params.column_keys"></span><strong>column_keys</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Alias.compile.params.column_keys">¶</a> – Used for INSERT and UPDATE statements, a list of
column names which should be present in the VALUES clause of the
compiled statement. If <tt class="docutils literal"><span class="pre">None</span></tt>, all columns from the target table
object are rendered.</li>
<li><span class="target" id="sqlalchemy.sql.expression.Alias.compile.params.dialect"></span><strong>dialect</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Alias.compile.params.dialect">¶</a> – A <tt class="docutils literal"><span class="pre">Dialect</span></tt> instance from which a <tt class="docutils literal"><span class="pre">Compiled</span></tt>
will be acquired. This argument takes precedence over the <cite>bind</cite>
argument as well as this <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a>‘s bound engine,
if any.</li>
<li><span class="target" id="sqlalchemy.sql.expression.Alias.compile.params.inline"></span><strong>inline</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Alias.compile.params.inline">¶</a> – Used for INSERT statements, for a dialect which does
not support inline retrieval of newly generated primary key
columns, will force the expression used to create the new primary
key value to be rendered inline within the INSERT statement’s
VALUES clause. This typically refers to Sequence execution but may
also refer to any server-side default generation function
associated with a primary key <cite>Column</cite>.</li>
<li><span class="target" id="sqlalchemy.sql.expression.Alias.compile.params.compile_kwargs"></span><strong>compile_kwargs</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Alias.compile.params.compile_kwargs">¶</a> – <p>optional dictionary of additional parameters
that will be passed through to the compiler within all “visit”
methods. This allows any custom flag to be passed through to
a custom compilation construct, for example. It is also used
for the case of passing the <tt class="docutils literal"><span class="pre">literal_binds</span></tt> flag through:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy.sql</span> <span class="kn">import</span> <span class="n">table</span><span class="p">,</span> <span class="n">column</span><span class="p">,</span> <span class="n">select</span>
<span class="n">t</span> <span class="o">=</span> <span class="n">table</span><span class="p">(</span><span class="s">'t'</span><span class="p">,</span> <span class="n">column</span><span class="p">(</span><span class="s">'x'</span><span class="p">))</span>
<span class="n">s</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">t</span><span class="p">])</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="n">t</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">x</span> <span class="o">==</span> <span class="mi">5</span><span class="p">)</span>
<span class="k">print</span> <span class="n">s</span><span class="o">.</span><span class="n">compile</span><span class="p">(</span><span class="n">compile_kwargs</span><span class="o">=</span><span class="p">{</span><span class="s">"literal_binds"</span><span class="p">:</span> <span class="bp">True</span><span class="p">})</span></pre></div>
</div>
<div class="versionadded">
<p><span>New in version 0.9.0.</span></p>
</div>
</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="../faq.html#faq-sql-expression-string"><em>How do I render SQL expressions as strings, possibly with bound parameters inlined?</em></a></p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Alias.correspond_on_equivalents">
<tt class="descname">correspond_on_equivalents</tt><big>(</big><em>column</em>, <em>equivalents</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Alias.correspond_on_equivalents" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.correspond_on_equivalents" title="sqlalchemy.sql.expression.FromClause.correspond_on_equivalents"><tt class="xref py py-meth docutils literal"><span class="pre">correspond_on_equivalents()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return corresponding_column for the given column, or if None
search for a match in the given dictionary.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Alias.corresponding_column">
<tt class="descname">corresponding_column</tt><big>(</big><em>column</em>, <em>require_embedded=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Alias.corresponding_column" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.corresponding_column" title="sqlalchemy.sql.expression.FromClause.corresponding_column"><tt class="xref py py-meth docutils literal"><span class="pre">corresponding_column()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Given a <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a>, return the exported
<a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> object from this <a class="reference internal" href="#sqlalchemy.sql.expression.Selectable" title="sqlalchemy.sql.expression.Selectable"><tt class="xref py py-class docutils literal"><span class="pre">Selectable</span></tt></a>
which corresponds to that original
<a class="reference internal" href="metadata.html#sqlalchemy.schema.Column" title="sqlalchemy.schema.Column"><tt class="xref py py-class docutils literal"><span class="pre">Column</span></tt></a> via a common ancestor
column.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.Alias.corresponding_column.params.column"></span><strong>column</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Alias.corresponding_column.params.column">¶</a> – the target <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> to be matched</li>
<li><span class="target" id="sqlalchemy.sql.expression.Alias.corresponding_column.params.require_embedded"></span><strong>require_embedded</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Alias.corresponding_column.params.require_embedded">¶</a> – only return corresponding columns for
the given <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a>, if the given
<a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> is actually present within a sub-element
of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>. Normally the column will match if
it merely shares a common ancestor with one of the exported
columns of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Alias.count">
<tt class="descname">count</tt><big>(</big><em>whereclause=None</em>, <em>**params</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Alias.count" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.count" title="sqlalchemy.sql.expression.FromClause.count"><tt class="xref py py-meth docutils literal"><span class="pre">count()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>return a SELECT COUNT generated against this
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.Alias.foreign_keys">
<tt class="descname">foreign_keys</tt><a class="headerlink" href="#sqlalchemy.sql.expression.Alias.foreign_keys" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.foreign_keys" title="sqlalchemy.sql.expression.FromClause.foreign_keys"><tt class="xref py py-attr docutils literal"><span class="pre">foreign_keys</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return the collection of ForeignKey objects which this
FromClause references.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Alias.join">
<tt class="descname">join</tt><big>(</big><em>right</em>, <em>onclause=None</em>, <em>isouter=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Alias.join" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">join()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return a <a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> from this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>
to another <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<p>E.g.:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="n">join</span>
<span class="n">j</span> <span class="o">=</span> <span class="n">user_table</span><span class="o">.</span><span class="n">join</span><span class="p">(</span><span class="n">address_table</span><span class="p">,</span>
<span class="n">user_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span> <span class="o">==</span> <span class="n">address_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">user_id</span><span class="p">)</span>
<span class="n">stmt</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">user_table</span><span class="p">])</span><span class="o">.</span><span class="n">select_from</span><span class="p">(</span><span class="n">j</span><span class="p">)</span></pre></div>
</div>
<p>would emit SQL along the lines of:</p>
<div class="highlight-python"><pre>SELECT user.id, user.name FROM user
JOIN address ON user.id = address.user_id</pre>
</div>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.Alias.join.params.right"></span><strong>right</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Alias.join.params.right">¶</a> – the right side of the join; this is any
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> object such as a <a class="reference internal" href="metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a> object, and
may also be a selectable-compatible object such as an ORM-mapped
class.</li>
<li><span class="target" id="sqlalchemy.sql.expression.Alias.join.params.onclause"></span><strong>onclause</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Alias.join.params.onclause">¶</a> – a SQL expression representing the ON clause of the
join. If left at <tt class="docutils literal"><span class="pre">None</span></tt>, <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a> will attempt to
join the two tables based on a foreign key relationship.</li>
<li><span class="target" id="sqlalchemy.sql.expression.Alias.join.params.isouter"></span><strong>isouter</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Alias.join.params.isouter">¶</a> – if True, render a LEFT OUTER JOIN, instead of JOIN.</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p><a class="reference internal" href="#sqlalchemy.sql.expression.join" title="sqlalchemy.sql.expression.join"><tt class="xref py py-func docutils literal"><span class="pre">join()</span></tt></a> - standalone function</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> - the type of object produced</p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Alias.outerjoin">
<tt class="descname">outerjoin</tt><big>(</big><em>right</em>, <em>onclause=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Alias.outerjoin" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.outerjoin" title="sqlalchemy.sql.expression.FromClause.outerjoin"><tt class="xref py py-meth docutils literal"><span class="pre">outerjoin()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return a <a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> from this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>
to another <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>, with the “isouter” flag set to
True.</p>
<p>E.g.:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="n">outerjoin</span>
<span class="n">j</span> <span class="o">=</span> <span class="n">user_table</span><span class="o">.</span><span class="n">outerjoin</span><span class="p">(</span><span class="n">address_table</span><span class="p">,</span>
<span class="n">user_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span> <span class="o">==</span> <span class="n">address_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">user_id</span><span class="p">)</span></pre></div>
</div>
<p>The above is equivalent to:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">j</span> <span class="o">=</span> <span class="n">user_table</span><span class="o">.</span><span class="n">join</span><span class="p">(</span>
<span class="n">address_table</span><span class="p">,</span>
<span class="n">user_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span> <span class="o">==</span> <span class="n">address_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">user_id</span><span class="p">,</span>
<span class="n">isouter</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span></pre></div>
</div>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.Alias.outerjoin.params.right"></span><strong>right</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Alias.outerjoin.params.right">¶</a> – the right side of the join; this is any
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> object such as a <a class="reference internal" href="metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a> object, and
may also be a selectable-compatible object such as an ORM-mapped
class.</li>
<li><span class="target" id="sqlalchemy.sql.expression.Alias.outerjoin.params.onclause"></span><strong>onclause</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Alias.outerjoin.params.onclause">¶</a> – a SQL expression representing the ON clause of the
join. If left at <tt class="docutils literal"><span class="pre">None</span></tt>, <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a> will attempt to
join the two tables based on a foreign key relationship.</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p><a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a></p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a></p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Alias.params">
<tt class="descname">params</tt><big>(</big><em>*optionaldict</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Alias.params" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.params" title="sqlalchemy.sql.expression.ClauseElement.params"><tt class="xref py py-meth docutils literal"><span class="pre">params()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Return a copy with <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.bindparam" title="sqlalchemy.sql.expression.bindparam"><tt class="xref py py-func docutils literal"><span class="pre">bindparam()</span></tt></a> elements replaced.</p>
<p>Returns a copy of this ClauseElement with <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.bindparam" title="sqlalchemy.sql.expression.bindparam"><tt class="xref py py-func docutils literal"><span class="pre">bindparam()</span></tt></a>
elements replaced with values taken from the given dictionary:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="n">clause</span> <span class="o">=</span> <span class="n">column</span><span class="p">(</span><span class="s">'x'</span><span class="p">)</span> <span class="o">+</span> <span class="n">bindparam</span><span class="p">(</span><span class="s">'foo'</span><span class="p">)</span>
<span class="gp">>>> </span><span class="k">print</span> <span class="n">clause</span><span class="o">.</span><span class="n">compile</span><span class="p">()</span><span class="o">.</span><span class="n">params</span>
<span class="go">{'foo':None}</span>
<span class="gp">>>> </span><span class="k">print</span> <span class="n">clause</span><span class="o">.</span><span class="n">params</span><span class="p">({</span><span class="s">'foo'</span><span class="p">:</span><span class="mi">7</span><span class="p">})</span><span class="o">.</span><span class="n">compile</span><span class="p">()</span><span class="o">.</span><span class="n">params</span>
<span class="go">{'foo':7}</span></pre></div>
</div>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.Alias.primary_key">
<tt class="descname">primary_key</tt><a class="headerlink" href="#sqlalchemy.sql.expression.Alias.primary_key" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.primary_key" title="sqlalchemy.sql.expression.FromClause.primary_key"><tt class="xref py py-attr docutils literal"><span class="pre">primary_key</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return the collection of Column objects which comprise the
primary key of this FromClause.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Alias.replace_selectable">
<tt class="descname">replace_selectable</tt><big>(</big><em>old</em>, <em>alias</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Alias.replace_selectable" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.replace_selectable" title="sqlalchemy.sql.expression.FromClause.replace_selectable"><tt class="xref py py-meth docutils literal"><span class="pre">replace_selectable()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>replace all occurrences of FromClause ‘old’ with the given Alias
object, returning a copy of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Alias.select">
<tt class="descname">select</tt><big>(</big><em>whereclause=None</em>, <em>**params</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Alias.select" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.select" title="sqlalchemy.sql.expression.FromClause.select"><tt class="xref py py-meth docutils literal"><span class="pre">select()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>return a SELECT of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a> - general purpose
method which allows for arbitrary column lists.</p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Alias.self_group">
<tt class="descname">self_group</tt><big>(</big><em>against=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Alias.self_group" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.self_group" title="sqlalchemy.sql.expression.ClauseElement.self_group"><tt class="xref py py-meth docutils literal"><span class="pre">self_group()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Apply a ‘grouping’ to this <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a>.</p>
<p>This method is overridden by subclasses to return a
“grouping” construct, i.e. parenthesis. In particular
it’s used by “binary” expressions to provide a grouping
around themselves when placed into a larger expression,
as well as by <a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a> constructs when placed into
the FROM clause of another <a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a>. (Note that
subqueries should be normally created using the
<a class="reference internal" href="#sqlalchemy.sql.expression.Select.alias" title="sqlalchemy.sql.expression.Select.alias"><tt class="xref py py-meth docutils literal"><span class="pre">Select.alias()</span></tt></a> method, as many platforms require
nested SELECT statements to be named).</p>
<p>As expressions are composed together, the application of
<a class="reference internal" href="#sqlalchemy.sql.expression.Alias.self_group" title="sqlalchemy.sql.expression.Alias.self_group"><tt class="xref py py-meth docutils literal"><span class="pre">self_group()</span></tt></a> is automatic - end-user code should never
need to use this method directly. Note that SQLAlchemy’s
clause constructs take operator precedence into account -
so parenthesis might not be needed, for example, in
an expression like <tt class="docutils literal"><span class="pre">x</span> <span class="pre">OR</span> <span class="pre">(y</span> <span class="pre">AND</span> <span class="pre">z)</span></tt> - AND takes precedence
over OR.</p>
<p>The base <a class="reference internal" href="#sqlalchemy.sql.expression.Alias.self_group" title="sqlalchemy.sql.expression.Alias.self_group"><tt class="xref py py-meth docutils literal"><span class="pre">self_group()</span></tt></a> method of <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a>
just returns self.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Alias.unique_params">
<tt class="descname">unique_params</tt><big>(</big><em>*optionaldict</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Alias.unique_params" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.unique_params" title="sqlalchemy.sql.expression.ClauseElement.unique_params"><tt class="xref py py-meth docutils literal"><span class="pre">unique_params()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Return a copy with <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.bindparam" title="sqlalchemy.sql.expression.bindparam"><tt class="xref py py-func docutils literal"><span class="pre">bindparam()</span></tt></a> elements replaced.</p>
<p>Same functionality as <tt class="docutils literal"><span class="pre">params()</span></tt>, except adds <cite>unique=True</cite>
to affected bind parameters so that multiple statements can be
used.</p>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.sql.expression.CompoundSelect">
<em class="property">class </em><tt class="descclassname">sqlalchemy.sql.expression.</tt><tt class="descname">CompoundSelect</tt><big>(</big><em>keyword</em>, <em>*selects</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect" title="sqlalchemy.sql.expression.GenerativeSelect"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.sql.expression.GenerativeSelect</span></tt></a></p>
<dl class="docutils">
<dt>Forms the basis of <tt class="docutils literal"><span class="pre">UNION</span></tt>, <tt class="docutils literal"><span class="pre">UNION</span> <span class="pre">ALL</span></tt>, and other</dt>
<dd>SELECT-based set operations.</dd>
</dl>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p><a class="reference internal" href="#sqlalchemy.sql.expression.union" title="sqlalchemy.sql.expression.union"><tt class="xref py py-func docutils literal"><span class="pre">union()</span></tt></a></p>
<p><a class="reference internal" href="#sqlalchemy.sql.expression.union_all" title="sqlalchemy.sql.expression.union_all"><tt class="xref py py-func docutils literal"><span class="pre">union_all()</span></tt></a></p>
<p><a class="reference internal" href="#sqlalchemy.sql.expression.intersect" title="sqlalchemy.sql.expression.intersect"><tt class="xref py py-func docutils literal"><span class="pre">intersect()</span></tt></a></p>
<p><a class="reference internal" href="#sqlalchemy.sql.expression.intersect_all" title="sqlalchemy.sql.expression.intersect_all"><tt class="xref py py-func docutils literal"><span class="pre">intersect_all()</span></tt></a></p>
<p><tt class="xref py py-func docutils literal"><span class="pre">except()</span></tt></p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.except_all" title="sqlalchemy.sql.expression.except_all"><tt class="xref py py-func docutils literal"><span class="pre">except_all()</span></tt></a></p>
</div>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CompoundSelect.alias">
<tt class="descname">alias</tt><big>(</big><em>name=None</em>, <em>flat=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.alias" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.alias" title="sqlalchemy.sql.expression.FromClause.alias"><tt class="xref py py-meth docutils literal"><span class="pre">alias()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>return an alias of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<p>This is shorthand for calling:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="n">alias</span>
<span class="n">a</span> <span class="o">=</span> <span class="n">alias</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">name</span><span class="o">=</span><span class="n">name</span><span class="p">)</span></pre></div>
</div>
<p>See <a class="reference internal" href="#sqlalchemy.sql.expression.alias" title="sqlalchemy.sql.expression.alias"><tt class="xref py py-func docutils literal"><span class="pre">alias()</span></tt></a> for details.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CompoundSelect.append_group_by">
<tt class="descname">append_group_by</tt><big>(</big><em>*clauses</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.append_group_by" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.append_group_by" title="sqlalchemy.sql.expression.GenerativeSelect.append_group_by"><tt class="xref py py-meth docutils literal"><span class="pre">append_group_by()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect" title="sqlalchemy.sql.expression.GenerativeSelect"><tt class="xref py py-class docutils literal"><span class="pre">GenerativeSelect</span></tt></a></div>
<p>Append the given GROUP BY criterion applied to this selectable.</p>
<p>The criterion will be appended to any pre-existing GROUP BY criterion.</p>
<p>This is an <strong>in-place</strong> mutation method; the
<a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.group_by" title="sqlalchemy.sql.expression.GenerativeSelect.group_by"><tt class="xref py py-meth docutils literal"><span class="pre">group_by()</span></tt></a> method is preferred, as it
provides standard <a class="reference internal" href="../glossary.html#term-method-chaining"><em class="xref std std-term">method chaining</em></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CompoundSelect.append_order_by">
<tt class="descname">append_order_by</tt><big>(</big><em>*clauses</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.append_order_by" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.append_order_by" title="sqlalchemy.sql.expression.GenerativeSelect.append_order_by"><tt class="xref py py-meth docutils literal"><span class="pre">append_order_by()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect" title="sqlalchemy.sql.expression.GenerativeSelect"><tt class="xref py py-class docutils literal"><span class="pre">GenerativeSelect</span></tt></a></div>
<p>Append the given ORDER BY criterion applied to this selectable.</p>
<p>The criterion will be appended to any pre-existing ORDER BY criterion.</p>
<p>This is an <strong>in-place</strong> mutation method; the
<a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.order_by" title="sqlalchemy.sql.expression.GenerativeSelect.order_by"><tt class="xref py py-meth docutils literal"><span class="pre">order_by()</span></tt></a> method is preferred, as it
provides standard <a class="reference internal" href="../glossary.html#term-method-chaining"><em class="xref std std-term">method chaining</em></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CompoundSelect.apply_labels">
<tt class="descname">apply_labels</tt><big>(</big><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.apply_labels" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.apply_labels" title="sqlalchemy.sql.expression.GenerativeSelect.apply_labels"><tt class="xref py py-meth docutils literal"><span class="pre">apply_labels()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect" title="sqlalchemy.sql.expression.GenerativeSelect"><tt class="xref py py-class docutils literal"><span class="pre">GenerativeSelect</span></tt></a></div>
<p>return a new selectable with the ‘use_labels’ flag set to True.</p>
<p>This will result in column expressions being generated using labels
against their table name, such as “SELECT somecolumn AS
tablename_somecolumn”. This allows selectables which contain multiple
FROM clauses to produce a unique set of column names regardless of
name conflicts among the individual FROM clauses.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CompoundSelect.as_scalar">
<tt class="descname">as_scalar</tt><big>(</big><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.as_scalar" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase.as_scalar" title="sqlalchemy.sql.expression.SelectBase.as_scalar"><tt class="xref py py-meth docutils literal"><span class="pre">as_scalar()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase" title="sqlalchemy.sql.expression.SelectBase"><tt class="xref py py-class docutils literal"><span class="pre">SelectBase</span></tt></a></div>
<p>return a ‘scalar’ representation of this selectable, which can be
used as a column expression.</p>
<p>Typically, a select statement which has only one column in its columns
clause is eligible to be used as a scalar expression.</p>
<p>The returned object is an instance of
<a class="reference internal" href="#sqlalchemy.sql.expression.ScalarSelect" title="sqlalchemy.sql.expression.ScalarSelect"><tt class="xref py py-class docutils literal"><span class="pre">ScalarSelect</span></tt></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CompoundSelect.autocommit">
<tt class="descname">autocommit</tt><big>(</big><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.autocommit" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase.autocommit" title="sqlalchemy.sql.expression.SelectBase.autocommit"><tt class="xref py py-meth docutils literal"><span class="pre">autocommit()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase" title="sqlalchemy.sql.expression.SelectBase"><tt class="xref py py-class docutils literal"><span class="pre">SelectBase</span></tt></a></div>
<p>return a new selectable with the ‘autocommit’ flag set to
True.</p>
<div class="deprecated">
<p><span>Deprecated since version 0.6: </span><tt class="docutils literal"><span class="pre">autocommit()</span></tt> is deprecated. Use <a class="reference internal" href="#sqlalchemy.sql.expression.Executable.execution_options" title="sqlalchemy.sql.expression.Executable.execution_options"><tt class="xref py py-meth docutils literal"><span class="pre">Executable.execution_options()</span></tt></a> with the ‘autocommit’ flag.</p>
</div>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.CompoundSelect.c">
<tt class="descname">c</tt><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.c" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.c" title="sqlalchemy.sql.expression.FromClause.c"><tt class="xref py py-attr docutils literal"><span class="pre">c</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>An alias for the <a class="reference internal" href="#sqlalchemy.sql.expression.CompoundSelect.columns" title="sqlalchemy.sql.expression.CompoundSelect.columns"><tt class="xref py py-attr docutils literal"><span class="pre">columns</span></tt></a> attribute.</p>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.CompoundSelect.columns">
<tt class="descname">columns</tt><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.columns" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.columns" title="sqlalchemy.sql.expression.FromClause.columns"><tt class="xref py py-attr docutils literal"><span class="pre">columns</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>A named-based collection of <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> objects
maintained by this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<p>The <a class="reference internal" href="#sqlalchemy.sql.expression.CompoundSelect.columns" title="sqlalchemy.sql.expression.CompoundSelect.columns"><tt class="xref py py-attr docutils literal"><span class="pre">columns</span></tt></a>, or <a class="reference internal" href="#sqlalchemy.sql.expression.CompoundSelect.c" title="sqlalchemy.sql.expression.CompoundSelect.c"><tt class="xref py py-attr docutils literal"><span class="pre">c</span></tt></a> collection, is the gateway
to the construction of SQL expressions using table-bound or
other selectable-bound columns:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">select</span><span class="p">([</span><span class="n">mytable</span><span class="p">])</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="n">mytable</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">somecolumn</span> <span class="o">==</span> <span class="mi">5</span><span class="p">)</span></pre></div>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CompoundSelect.compare">
<tt class="descname">compare</tt><big>(</big><em>other</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.compare" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.compare" title="sqlalchemy.sql.expression.ClauseElement.compare"><tt class="xref py py-meth docutils literal"><span class="pre">compare()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Compare this ClauseElement to the given ClauseElement.</p>
<p>Subclasses should override the default behavior, which is a
straight identity comparison.</p>
<p>**kw are arguments consumed by subclass compare() methods and
may be used to modify the criteria for comparison.
(see <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a>)</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CompoundSelect.compile">
<tt class="descname">compile</tt><big>(</big><em>bind=None</em>, <em>dialect=None</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.compile" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.compile" title="sqlalchemy.sql.expression.ClauseElement.compile"><tt class="xref py py-meth docutils literal"><span class="pre">compile()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Compile this SQL expression.</p>
<p>The return value is a <a class="reference internal" href="internals.html#sqlalchemy.engine.interfaces.Compiled" title="sqlalchemy.engine.interfaces.Compiled"><tt class="xref py py-class docutils literal"><span class="pre">Compiled</span></tt></a> object.
Calling <tt class="docutils literal"><span class="pre">str()</span></tt> or <tt class="docutils literal"><span class="pre">unicode()</span></tt> on the returned value will yield a
string representation of the result. The
<a class="reference internal" href="internals.html#sqlalchemy.engine.interfaces.Compiled" title="sqlalchemy.engine.interfaces.Compiled"><tt class="xref py py-class docutils literal"><span class="pre">Compiled</span></tt></a> object also can return a
dictionary of bind parameter names and values
using the <tt class="docutils literal"><span class="pre">params</span></tt> accessor.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.CompoundSelect.compile.params.bind"></span><strong>bind</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CompoundSelect.compile.params.bind">¶</a> – An <tt class="docutils literal"><span class="pre">Engine</span></tt> or <tt class="docutils literal"><span class="pre">Connection</span></tt> from which a
<tt class="docutils literal"><span class="pre">Compiled</span></tt> will be acquired. This argument takes precedence over
this <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a>‘s bound engine, if any.</li>
<li><span class="target" id="sqlalchemy.sql.expression.CompoundSelect.compile.params.column_keys"></span><strong>column_keys</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CompoundSelect.compile.params.column_keys">¶</a> – Used for INSERT and UPDATE statements, a list of
column names which should be present in the VALUES clause of the
compiled statement. If <tt class="docutils literal"><span class="pre">None</span></tt>, all columns from the target table
object are rendered.</li>
<li><span class="target" id="sqlalchemy.sql.expression.CompoundSelect.compile.params.dialect"></span><strong>dialect</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CompoundSelect.compile.params.dialect">¶</a> – A <tt class="docutils literal"><span class="pre">Dialect</span></tt> instance from which a <tt class="docutils literal"><span class="pre">Compiled</span></tt>
will be acquired. This argument takes precedence over the <cite>bind</cite>
argument as well as this <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a>‘s bound engine,
if any.</li>
<li><span class="target" id="sqlalchemy.sql.expression.CompoundSelect.compile.params.inline"></span><strong>inline</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CompoundSelect.compile.params.inline">¶</a> – Used for INSERT statements, for a dialect which does
not support inline retrieval of newly generated primary key
columns, will force the expression used to create the new primary
key value to be rendered inline within the INSERT statement’s
VALUES clause. This typically refers to Sequence execution but may
also refer to any server-side default generation function
associated with a primary key <cite>Column</cite>.</li>
<li><span class="target" id="sqlalchemy.sql.expression.CompoundSelect.compile.params.compile_kwargs"></span><strong>compile_kwargs</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CompoundSelect.compile.params.compile_kwargs">¶</a> – <p>optional dictionary of additional parameters
that will be passed through to the compiler within all “visit”
methods. This allows any custom flag to be passed through to
a custom compilation construct, for example. It is also used
for the case of passing the <tt class="docutils literal"><span class="pre">literal_binds</span></tt> flag through:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy.sql</span> <span class="kn">import</span> <span class="n">table</span><span class="p">,</span> <span class="n">column</span><span class="p">,</span> <span class="n">select</span>
<span class="n">t</span> <span class="o">=</span> <span class="n">table</span><span class="p">(</span><span class="s">'t'</span><span class="p">,</span> <span class="n">column</span><span class="p">(</span><span class="s">'x'</span><span class="p">))</span>
<span class="n">s</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">t</span><span class="p">])</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="n">t</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">x</span> <span class="o">==</span> <span class="mi">5</span><span class="p">)</span>
<span class="k">print</span> <span class="n">s</span><span class="o">.</span><span class="n">compile</span><span class="p">(</span><span class="n">compile_kwargs</span><span class="o">=</span><span class="p">{</span><span class="s">"literal_binds"</span><span class="p">:</span> <span class="bp">True</span><span class="p">})</span></pre></div>
</div>
<div class="versionadded">
<p><span>New in version 0.9.0.</span></p>
</div>
</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="../faq.html#faq-sql-expression-string"><em>How do I render SQL expressions as strings, possibly with bound parameters inlined?</em></a></p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CompoundSelect.correspond_on_equivalents">
<tt class="descname">correspond_on_equivalents</tt><big>(</big><em>column</em>, <em>equivalents</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.correspond_on_equivalents" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.correspond_on_equivalents" title="sqlalchemy.sql.expression.FromClause.correspond_on_equivalents"><tt class="xref py py-meth docutils literal"><span class="pre">correspond_on_equivalents()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return corresponding_column for the given column, or if None
search for a match in the given dictionary.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CompoundSelect.corresponding_column">
<tt class="descname">corresponding_column</tt><big>(</big><em>column</em>, <em>require_embedded=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.corresponding_column" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.corresponding_column" title="sqlalchemy.sql.expression.FromClause.corresponding_column"><tt class="xref py py-meth docutils literal"><span class="pre">corresponding_column()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Given a <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a>, return the exported
<a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> object from this <a class="reference internal" href="#sqlalchemy.sql.expression.Selectable" title="sqlalchemy.sql.expression.Selectable"><tt class="xref py py-class docutils literal"><span class="pre">Selectable</span></tt></a>
which corresponds to that original
<a class="reference internal" href="metadata.html#sqlalchemy.schema.Column" title="sqlalchemy.schema.Column"><tt class="xref py py-class docutils literal"><span class="pre">Column</span></tt></a> via a common ancestor
column.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.CompoundSelect.corresponding_column.params.column"></span><strong>column</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CompoundSelect.corresponding_column.params.column">¶</a> – the target <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> to be matched</li>
<li><span class="target" id="sqlalchemy.sql.expression.CompoundSelect.corresponding_column.params.require_embedded"></span><strong>require_embedded</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CompoundSelect.corresponding_column.params.require_embedded">¶</a> – only return corresponding columns for
the given <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a>, if the given
<a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> is actually present within a sub-element
of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>. Normally the column will match if
it merely shares a common ancestor with one of the exported
columns of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CompoundSelect.count">
<tt class="descname">count</tt><big>(</big><em>whereclause=None</em>, <em>**params</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.count" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.count" title="sqlalchemy.sql.expression.FromClause.count"><tt class="xref py py-meth docutils literal"><span class="pre">count()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>return a SELECT COUNT generated against this
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CompoundSelect.cte">
<tt class="descname">cte</tt><big>(</big><em>name=None</em>, <em>recursive=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.cte" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase.cte" title="sqlalchemy.sql.expression.SelectBase.cte"><tt class="xref py py-meth docutils literal"><span class="pre">cte()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase" title="sqlalchemy.sql.expression.SelectBase"><tt class="xref py py-class docutils literal"><span class="pre">SelectBase</span></tt></a></div>
<p>Return a new <a class="reference internal" href="#sqlalchemy.sql.expression.CTE" title="sqlalchemy.sql.expression.CTE"><tt class="xref py py-class docutils literal"><span class="pre">CTE</span></tt></a>, or Common Table Expression instance.</p>
<p>Common table expressions are a SQL standard whereby SELECT
statements can draw upon secondary statements specified along
with the primary statement, using a clause called “WITH”.
Special semantics regarding UNION can also be employed to
allow “recursive” queries, where a SELECT statement can draw
upon the set of rows that have previously been selected.</p>
<p>SQLAlchemy detects <a class="reference internal" href="#sqlalchemy.sql.expression.CTE" title="sqlalchemy.sql.expression.CTE"><tt class="xref py py-class docutils literal"><span class="pre">CTE</span></tt></a> objects, which are treated
similarly to <a class="reference internal" href="#sqlalchemy.sql.expression.Alias" title="sqlalchemy.sql.expression.Alias"><tt class="xref py py-class docutils literal"><span class="pre">Alias</span></tt></a> objects, as special elements
to be delivered to the FROM clause of the statement as well
as to a WITH clause at the top of the statement.</p>
<div class="versionadded">
<p><span>New in version 0.7.6.</span></p>
</div>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.CompoundSelect.cte.params.name"></span><strong>name</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CompoundSelect.cte.params.name">¶</a> – name given to the common table expression. Like
<tt class="xref py py-meth docutils literal"><span class="pre">_FromClause.alias()</span></tt>, the name can be left as <tt class="docutils literal"><span class="pre">None</span></tt>
in which case an anonymous symbol will be used at query
compile time.</li>
<li><span class="target" id="sqlalchemy.sql.expression.CompoundSelect.cte.params.recursive"></span><strong>recursive</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CompoundSelect.cte.params.recursive">¶</a> – if <tt class="docutils literal"><span class="pre">True</span></tt>, will render <tt class="docutils literal"><span class="pre">WITH</span> <span class="pre">RECURSIVE</span></tt>.
A recursive common table expression is intended to be used in
conjunction with UNION ALL in order to derive rows
from those already selected.</li>
</ul>
</td>
</tr>
</tbody>
</table>
<p>The following examples illustrate two examples from
Postgresql’s documentation at
<a class="reference external" href="http://www.postgresql.org/docs/8.4/static/queries-with.html">http://www.postgresql.org/docs/8.4/static/queries-with.html</a>.</p>
<p>Example 1, non recursive:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="p">(</span><span class="n">Table</span><span class="p">,</span> <span class="n">Column</span><span class="p">,</span> <span class="n">String</span><span class="p">,</span> <span class="n">Integer</span><span class="p">,</span>
<span class="n">MetaData</span><span class="p">,</span> <span class="n">select</span><span class="p">,</span> <span class="n">func</span><span class="p">)</span>
<span class="n">metadata</span> <span class="o">=</span> <span class="n">MetaData</span><span class="p">()</span>
<span class="n">orders</span> <span class="o">=</span> <span class="n">Table</span><span class="p">(</span><span class="s">'orders'</span><span class="p">,</span> <span class="n">metadata</span><span class="p">,</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'region'</span><span class="p">,</span> <span class="n">String</span><span class="p">),</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'amount'</span><span class="p">,</span> <span class="n">Integer</span><span class="p">),</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'product'</span><span class="p">,</span> <span class="n">String</span><span class="p">),</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'quantity'</span><span class="p">,</span> <span class="n">Integer</span><span class="p">)</span>
<span class="p">)</span>
<span class="n">regional_sales</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span>
<span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">region</span><span class="p">,</span>
<span class="n">func</span><span class="o">.</span><span class="n">sum</span><span class="p">(</span><span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">amount</span><span class="p">)</span><span class="o">.</span><span class="n">label</span><span class="p">(</span><span class="s">'total_sales'</span><span class="p">)</span>
<span class="p">])</span><span class="o">.</span><span class="n">group_by</span><span class="p">(</span><span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">region</span><span class="p">)</span><span class="o">.</span><span class="n">cte</span><span class="p">(</span><span class="s">"regional_sales"</span><span class="p">)</span>
<span class="n">top_regions</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">regional_sales</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">region</span><span class="p">])</span><span class="o">.</span>\
<span class="n">where</span><span class="p">(</span>
<span class="n">regional_sales</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">total_sales</span> <span class="o">></span>
<span class="n">select</span><span class="p">([</span>
<span class="n">func</span><span class="o">.</span><span class="n">sum</span><span class="p">(</span><span class="n">regional_sales</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">total_sales</span><span class="p">)</span><span class="o">/</span><span class="mi">10</span>
<span class="p">])</span>
<span class="p">)</span><span class="o">.</span><span class="n">cte</span><span class="p">(</span><span class="s">"top_regions"</span><span class="p">)</span>
<span class="n">statement</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span>
<span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">region</span><span class="p">,</span>
<span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">product</span><span class="p">,</span>
<span class="n">func</span><span class="o">.</span><span class="n">sum</span><span class="p">(</span><span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">quantity</span><span class="p">)</span><span class="o">.</span><span class="n">label</span><span class="p">(</span><span class="s">"product_units"</span><span class="p">),</span>
<span class="n">func</span><span class="o">.</span><span class="n">sum</span><span class="p">(</span><span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">amount</span><span class="p">)</span><span class="o">.</span><span class="n">label</span><span class="p">(</span><span class="s">"product_sales"</span><span class="p">)</span>
<span class="p">])</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">region</span><span class="o">.</span><span class="n">in_</span><span class="p">(</span>
<span class="n">select</span><span class="p">([</span><span class="n">top_regions</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">region</span><span class="p">])</span>
<span class="p">))</span><span class="o">.</span><span class="n">group_by</span><span class="p">(</span><span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">region</span><span class="p">,</span> <span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">product</span><span class="p">)</span>
<span class="n">result</span> <span class="o">=</span> <span class="n">conn</span><span class="o">.</span><span class="n">execute</span><span class="p">(</span><span class="n">statement</span><span class="p">)</span><span class="o">.</span><span class="n">fetchall</span><span class="p">()</span></pre></div>
</div>
<p>Example 2, WITH RECURSIVE:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="p">(</span><span class="n">Table</span><span class="p">,</span> <span class="n">Column</span><span class="p">,</span> <span class="n">String</span><span class="p">,</span> <span class="n">Integer</span><span class="p">,</span>
<span class="n">MetaData</span><span class="p">,</span> <span class="n">select</span><span class="p">,</span> <span class="n">func</span><span class="p">)</span>
<span class="n">metadata</span> <span class="o">=</span> <span class="n">MetaData</span><span class="p">()</span>
<span class="n">parts</span> <span class="o">=</span> <span class="n">Table</span><span class="p">(</span><span class="s">'parts'</span><span class="p">,</span> <span class="n">metadata</span><span class="p">,</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'part'</span><span class="p">,</span> <span class="n">String</span><span class="p">),</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'sub_part'</span><span class="p">,</span> <span class="n">String</span><span class="p">),</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'quantity'</span><span class="p">,</span> <span class="n">Integer</span><span class="p">),</span>
<span class="p">)</span>
<span class="n">included_parts</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span>
<span class="n">parts</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">sub_part</span><span class="p">,</span>
<span class="n">parts</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">part</span><span class="p">,</span>
<span class="n">parts</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">quantity</span><span class="p">])</span><span class="o">.</span>\
<span class="n">where</span><span class="p">(</span><span class="n">parts</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">part</span><span class="o">==</span><span class="s">'our part'</span><span class="p">)</span><span class="o">.</span>\
<span class="n">cte</span><span class="p">(</span><span class="n">recursive</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span>
<span class="n">incl_alias</span> <span class="o">=</span> <span class="n">included_parts</span><span class="o">.</span><span class="n">alias</span><span class="p">()</span>
<span class="n">parts_alias</span> <span class="o">=</span> <span class="n">parts</span><span class="o">.</span><span class="n">alias</span><span class="p">()</span>
<span class="n">included_parts</span> <span class="o">=</span> <span class="n">included_parts</span><span class="o">.</span><span class="n">union_all</span><span class="p">(</span>
<span class="n">select</span><span class="p">([</span>
<span class="n">parts_alias</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">sub_part</span><span class="p">,</span>
<span class="n">parts_alias</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">part</span><span class="p">,</span>
<span class="n">parts_alias</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">quantity</span>
<span class="p">])</span><span class="o">.</span>
<span class="n">where</span><span class="p">(</span><span class="n">parts_alias</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">part</span><span class="o">==</span><span class="n">incl_alias</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">sub_part</span><span class="p">)</span>
<span class="p">)</span>
<span class="n">statement</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span>
<span class="n">included_parts</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">sub_part</span><span class="p">,</span>
<span class="n">func</span><span class="o">.</span><span class="n">sum</span><span class="p">(</span><span class="n">included_parts</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">quantity</span><span class="p">)</span><span class="o">.</span>
<span class="n">label</span><span class="p">(</span><span class="s">'total_quantity'</span><span class="p">)</span>
<span class="p">])</span><span class="o">.</span>\
<span class="n">group_by</span><span class="p">(</span><span class="n">included_parts</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">sub_part</span><span class="p">)</span>
<span class="n">result</span> <span class="o">=</span> <span class="n">conn</span><span class="o">.</span><span class="n">execute</span><span class="p">(</span><span class="n">statement</span><span class="p">)</span><span class="o">.</span><span class="n">fetchall</span><span class="p">()</span></pre></div>
</div>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="../orm/query.html#sqlalchemy.orm.query.Query.cte" title="sqlalchemy.orm.query.Query.cte"><tt class="xref py py-meth docutils literal"><span class="pre">orm.query.Query.cte()</span></tt></a> - ORM version of
<a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase.cte" title="sqlalchemy.sql.expression.SelectBase.cte"><tt class="xref py py-meth docutils literal"><span class="pre">SelectBase.cte()</span></tt></a>.</p>
</div>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.CompoundSelect.description">
<tt class="descname">description</tt><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.description" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.description" title="sqlalchemy.sql.expression.FromClause.description"><tt class="xref py py-attr docutils literal"><span class="pre">description</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>a brief description of this FromClause.</p>
<p>Used primarily for error message formatting.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CompoundSelect.execute">
<tt class="descname">execute</tt><big>(</big><em>*multiparams</em>, <em>**params</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.execute" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.Executable.execute" title="sqlalchemy.sql.expression.Executable.execute"><tt class="xref py py-meth docutils literal"><span class="pre">execute()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.Executable" title="sqlalchemy.sql.expression.Executable"><tt class="xref py py-class docutils literal"><span class="pre">Executable</span></tt></a></div>
<p>Compile and execute this <a class="reference internal" href="#sqlalchemy.sql.expression.Executable" title="sqlalchemy.sql.expression.Executable"><tt class="xref py py-class docutils literal"><span class="pre">Executable</span></tt></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CompoundSelect.execution_options">
<tt class="descname">execution_options</tt><big>(</big><em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.execution_options" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.Executable.execution_options" title="sqlalchemy.sql.expression.Executable.execution_options"><tt class="xref py py-meth docutils literal"><span class="pre">execution_options()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.Executable" title="sqlalchemy.sql.expression.Executable"><tt class="xref py py-class docutils literal"><span class="pre">Executable</span></tt></a></div>
<p>Set non-SQL options for the statement which take effect during
execution.</p>
<p>Execution options can be set on a per-statement or
per <a class="reference internal" href="connections.html#sqlalchemy.engine.Connection" title="sqlalchemy.engine.Connection"><tt class="xref py py-class docutils literal"><span class="pre">Connection</span></tt></a> basis. Additionally, the
<a class="reference internal" href="connections.html#sqlalchemy.engine.Engine" title="sqlalchemy.engine.Engine"><tt class="xref py py-class docutils literal"><span class="pre">Engine</span></tt></a> and ORM <a class="reference internal" href="../orm/query.html#sqlalchemy.orm.query.Query" title="sqlalchemy.orm.query.Query"><tt class="xref py py-class docutils literal"><span class="pre">Query</span></tt></a> objects provide
access to execution options which they in turn configure upon
connections.</p>
<p>The <a class="reference internal" href="#sqlalchemy.sql.expression.CompoundSelect.execution_options" title="sqlalchemy.sql.expression.CompoundSelect.execution_options"><tt class="xref py py-meth docutils literal"><span class="pre">execution_options()</span></tt></a> method is generative. A new
instance of this statement is returned that contains the options:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">statement</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">x</span><span class="p">,</span> <span class="n">table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">y</span><span class="p">])</span>
<span class="n">statement</span> <span class="o">=</span> <span class="n">statement</span><span class="o">.</span><span class="n">execution_options</span><span class="p">(</span><span class="n">autocommit</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span></pre></div>
</div>
<p>Note that only a subset of possible execution options can be applied
to a statement - these include “autocommit” and “stream_results”,
but not “isolation_level” or “compiled_cache”.
See <a class="reference internal" href="connections.html#sqlalchemy.engine.Connection.execution_options" title="sqlalchemy.engine.Connection.execution_options"><tt class="xref py py-meth docutils literal"><span class="pre">Connection.execution_options()</span></tt></a> for a full list of
possible options.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p><a class="reference internal" href="connections.html#sqlalchemy.engine.Connection.execution_options" title="sqlalchemy.engine.Connection.execution_options"><tt class="xref py py-meth docutils literal"><span class="pre">Connection.execution_options()</span></tt></a></p>
<p class="last"><a class="reference internal" href="../orm/query.html#sqlalchemy.orm.query.Query.execution_options" title="sqlalchemy.orm.query.Query.execution_options"><tt class="xref py py-meth docutils literal"><span class="pre">Query.execution_options()</span></tt></a></p>
</div>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.CompoundSelect.for_update">
<tt class="descname">for_update</tt><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.for_update" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.for_update" title="sqlalchemy.sql.expression.GenerativeSelect.for_update"><tt class="xref py py-attr docutils literal"><span class="pre">for_update</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect" title="sqlalchemy.sql.expression.GenerativeSelect"><tt class="xref py py-class docutils literal"><span class="pre">GenerativeSelect</span></tt></a></div>
<p>Provide legacy dialect support for the <tt class="docutils literal"><span class="pre">for_update</span></tt> attribute.</p>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.CompoundSelect.foreign_keys">
<tt class="descname">foreign_keys</tt><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.foreign_keys" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.foreign_keys" title="sqlalchemy.sql.expression.FromClause.foreign_keys"><tt class="xref py py-attr docutils literal"><span class="pre">foreign_keys</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return the collection of ForeignKey objects which this
FromClause references.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CompoundSelect.group_by">
<tt class="descname">group_by</tt><big>(</big><em>*clauses</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.group_by" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.group_by" title="sqlalchemy.sql.expression.GenerativeSelect.group_by"><tt class="xref py py-meth docutils literal"><span class="pre">group_by()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect" title="sqlalchemy.sql.expression.GenerativeSelect"><tt class="xref py py-class docutils literal"><span class="pre">GenerativeSelect</span></tt></a></div>
<p>return a new selectable with the given list of GROUP BY
criterion applied.</p>
<p>The criterion will be appended to any pre-existing GROUP BY
criterion.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CompoundSelect.join">
<tt class="descname">join</tt><big>(</big><em>right</em>, <em>onclause=None</em>, <em>isouter=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.join" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">join()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return a <a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> from this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>
to another <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<p>E.g.:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="n">join</span>
<span class="n">j</span> <span class="o">=</span> <span class="n">user_table</span><span class="o">.</span><span class="n">join</span><span class="p">(</span><span class="n">address_table</span><span class="p">,</span>
<span class="n">user_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span> <span class="o">==</span> <span class="n">address_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">user_id</span><span class="p">)</span>
<span class="n">stmt</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">user_table</span><span class="p">])</span><span class="o">.</span><span class="n">select_from</span><span class="p">(</span><span class="n">j</span><span class="p">)</span></pre></div>
</div>
<p>would emit SQL along the lines of:</p>
<div class="highlight-python"><pre>SELECT user.id, user.name FROM user
JOIN address ON user.id = address.user_id</pre>
</div>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.CompoundSelect.join.params.right"></span><strong>right</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CompoundSelect.join.params.right">¶</a> – the right side of the join; this is any
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> object such as a <a class="reference internal" href="metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a> object, and
may also be a selectable-compatible object such as an ORM-mapped
class.</li>
<li><span class="target" id="sqlalchemy.sql.expression.CompoundSelect.join.params.onclause"></span><strong>onclause</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CompoundSelect.join.params.onclause">¶</a> – a SQL expression representing the ON clause of the
join. If left at <tt class="docutils literal"><span class="pre">None</span></tt>, <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a> will attempt to
join the two tables based on a foreign key relationship.</li>
<li><span class="target" id="sqlalchemy.sql.expression.CompoundSelect.join.params.isouter"></span><strong>isouter</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CompoundSelect.join.params.isouter">¶</a> – if True, render a LEFT OUTER JOIN, instead of JOIN.</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p><a class="reference internal" href="#sqlalchemy.sql.expression.join" title="sqlalchemy.sql.expression.join"><tt class="xref py py-func docutils literal"><span class="pre">join()</span></tt></a> - standalone function</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> - the type of object produced</p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CompoundSelect.label">
<tt class="descname">label</tt><big>(</big><em>name</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.label" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase.label" title="sqlalchemy.sql.expression.SelectBase.label"><tt class="xref py py-meth docutils literal"><span class="pre">label()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase" title="sqlalchemy.sql.expression.SelectBase"><tt class="xref py py-class docutils literal"><span class="pre">SelectBase</span></tt></a></div>
<p>return a ‘scalar’ representation of this selectable, embedded as a
subquery with a label.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase.as_scalar" title="sqlalchemy.sql.expression.SelectBase.as_scalar"><tt class="xref py py-meth docutils literal"><span class="pre">as_scalar()</span></tt></a>.</p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CompoundSelect.limit">
<tt class="descname">limit</tt><big>(</big><em>limit</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.limit" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.limit" title="sqlalchemy.sql.expression.GenerativeSelect.limit"><tt class="xref py py-meth docutils literal"><span class="pre">limit()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect" title="sqlalchemy.sql.expression.GenerativeSelect"><tt class="xref py py-class docutils literal"><span class="pre">GenerativeSelect</span></tt></a></div>
<p>return a new selectable with the given LIMIT criterion
applied.</p>
<p>This is a numerical value which usually renders as a <tt class="docutils literal"><span class="pre">LIMIT</span></tt>
expression in the resulting select. Backends that don’t
support <tt class="docutils literal"><span class="pre">LIMIT</span></tt> will attempt to provide similar
functionality.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><span class="target" id="sqlalchemy.sql.expression.CompoundSelect.limit.params.limit"></span><strong>limit</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CompoundSelect.limit.params.limit">¶</a> – an integer LIMIT parameter.</td>
</tr>
</tbody>
</table>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CompoundSelect.offset">
<tt class="descname">offset</tt><big>(</big><em>offset</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.offset" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.offset" title="sqlalchemy.sql.expression.GenerativeSelect.offset"><tt class="xref py py-meth docutils literal"><span class="pre">offset()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect" title="sqlalchemy.sql.expression.GenerativeSelect"><tt class="xref py py-class docutils literal"><span class="pre">GenerativeSelect</span></tt></a></div>
<p>return a new selectable with the given OFFSET criterion
applied.</p>
<p>This is a numeric value which usually renders as an <tt class="docutils literal"><span class="pre">OFFSET</span></tt>
expression in the resulting select. Backends that don’t
support <tt class="docutils literal"><span class="pre">OFFSET</span></tt> will attempt to provide similar
functionality.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><span class="target" id="sqlalchemy.sql.expression.CompoundSelect.offset.params.offset"></span><strong>offset</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CompoundSelect.offset.params.offset">¶</a> – an integer OFFSET parameter.</td>
</tr>
</tbody>
</table>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CompoundSelect.order_by">
<tt class="descname">order_by</tt><big>(</big><em>*clauses</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.order_by" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.order_by" title="sqlalchemy.sql.expression.GenerativeSelect.order_by"><tt class="xref py py-meth docutils literal"><span class="pre">order_by()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect" title="sqlalchemy.sql.expression.GenerativeSelect"><tt class="xref py py-class docutils literal"><span class="pre">GenerativeSelect</span></tt></a></div>
<p>return a new selectable with the given list of ORDER BY
criterion applied.</p>
<p>The criterion will be appended to any pre-existing ORDER BY
criterion.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CompoundSelect.outerjoin">
<tt class="descname">outerjoin</tt><big>(</big><em>right</em>, <em>onclause=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.outerjoin" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.outerjoin" title="sqlalchemy.sql.expression.FromClause.outerjoin"><tt class="xref py py-meth docutils literal"><span class="pre">outerjoin()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return a <a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> from this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>
to another <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>, with the “isouter” flag set to
True.</p>
<p>E.g.:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="n">outerjoin</span>
<span class="n">j</span> <span class="o">=</span> <span class="n">user_table</span><span class="o">.</span><span class="n">outerjoin</span><span class="p">(</span><span class="n">address_table</span><span class="p">,</span>
<span class="n">user_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span> <span class="o">==</span> <span class="n">address_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">user_id</span><span class="p">)</span></pre></div>
</div>
<p>The above is equivalent to:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">j</span> <span class="o">=</span> <span class="n">user_table</span><span class="o">.</span><span class="n">join</span><span class="p">(</span>
<span class="n">address_table</span><span class="p">,</span>
<span class="n">user_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span> <span class="o">==</span> <span class="n">address_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">user_id</span><span class="p">,</span>
<span class="n">isouter</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span></pre></div>
</div>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.CompoundSelect.outerjoin.params.right"></span><strong>right</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CompoundSelect.outerjoin.params.right">¶</a> – the right side of the join; this is any
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> object such as a <a class="reference internal" href="metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a> object, and
may also be a selectable-compatible object such as an ORM-mapped
class.</li>
<li><span class="target" id="sqlalchemy.sql.expression.CompoundSelect.outerjoin.params.onclause"></span><strong>onclause</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CompoundSelect.outerjoin.params.onclause">¶</a> – a SQL expression representing the ON clause of the
join. If left at <tt class="docutils literal"><span class="pre">None</span></tt>, <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a> will attempt to
join the two tables based on a foreign key relationship.</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p><a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a></p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a></p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CompoundSelect.params">
<tt class="descname">params</tt><big>(</big><em>*optionaldict</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.params" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.params" title="sqlalchemy.sql.expression.ClauseElement.params"><tt class="xref py py-meth docutils literal"><span class="pre">params()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Return a copy with <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.bindparam" title="sqlalchemy.sql.expression.bindparam"><tt class="xref py py-func docutils literal"><span class="pre">bindparam()</span></tt></a> elements replaced.</p>
<p>Returns a copy of this ClauseElement with <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.bindparam" title="sqlalchemy.sql.expression.bindparam"><tt class="xref py py-func docutils literal"><span class="pre">bindparam()</span></tt></a>
elements replaced with values taken from the given dictionary:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="n">clause</span> <span class="o">=</span> <span class="n">column</span><span class="p">(</span><span class="s">'x'</span><span class="p">)</span> <span class="o">+</span> <span class="n">bindparam</span><span class="p">(</span><span class="s">'foo'</span><span class="p">)</span>
<span class="gp">>>> </span><span class="k">print</span> <span class="n">clause</span><span class="o">.</span><span class="n">compile</span><span class="p">()</span><span class="o">.</span><span class="n">params</span>
<span class="go">{'foo':None}</span>
<span class="gp">>>> </span><span class="k">print</span> <span class="n">clause</span><span class="o">.</span><span class="n">params</span><span class="p">({</span><span class="s">'foo'</span><span class="p">:</span><span class="mi">7</span><span class="p">})</span><span class="o">.</span><span class="n">compile</span><span class="p">()</span><span class="o">.</span><span class="n">params</span>
<span class="go">{'foo':7}</span></pre></div>
</div>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.CompoundSelect.primary_key">
<tt class="descname">primary_key</tt><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.primary_key" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.primary_key" title="sqlalchemy.sql.expression.FromClause.primary_key"><tt class="xref py py-attr docutils literal"><span class="pre">primary_key</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return the collection of Column objects which comprise the
primary key of this FromClause.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CompoundSelect.replace_selectable">
<tt class="descname">replace_selectable</tt><big>(</big><em>old</em>, <em>alias</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.replace_selectable" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.replace_selectable" title="sqlalchemy.sql.expression.FromClause.replace_selectable"><tt class="xref py py-meth docutils literal"><span class="pre">replace_selectable()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>replace all occurrences of FromClause ‘old’ with the given Alias
object, returning a copy of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CompoundSelect.scalar">
<tt class="descname">scalar</tt><big>(</big><em>*multiparams</em>, <em>**params</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.scalar" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.Executable.scalar" title="sqlalchemy.sql.expression.Executable.scalar"><tt class="xref py py-meth docutils literal"><span class="pre">scalar()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.Executable" title="sqlalchemy.sql.expression.Executable"><tt class="xref py py-class docutils literal"><span class="pre">Executable</span></tt></a></div>
<p>Compile and execute this <a class="reference internal" href="#sqlalchemy.sql.expression.Executable" title="sqlalchemy.sql.expression.Executable"><tt class="xref py py-class docutils literal"><span class="pre">Executable</span></tt></a>, returning the
result’s scalar representation.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CompoundSelect.select">
<tt class="descname">select</tt><big>(</big><em>whereclause=None</em>, <em>**params</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.select" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.select" title="sqlalchemy.sql.expression.FromClause.select"><tt class="xref py py-meth docutils literal"><span class="pre">select()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>return a SELECT of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a> - general purpose
method which allows for arbitrary column lists.</p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CompoundSelect.unique_params">
<tt class="descname">unique_params</tt><big>(</big><em>*optionaldict</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.unique_params" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.unique_params" title="sqlalchemy.sql.expression.ClauseElement.unique_params"><tt class="xref py py-meth docutils literal"><span class="pre">unique_params()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Return a copy with <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.bindparam" title="sqlalchemy.sql.expression.bindparam"><tt class="xref py py-func docutils literal"><span class="pre">bindparam()</span></tt></a> elements replaced.</p>
<p>Same functionality as <tt class="docutils literal"><span class="pre">params()</span></tt>, except adds <cite>unique=True</cite>
to affected bind parameters so that multiple statements can be
used.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CompoundSelect.with_for_update">
<tt class="descname">with_for_update</tt><big>(</big><em>nowait=False</em>, <em>read=False</em>, <em>of=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CompoundSelect.with_for_update" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.with_for_update" title="sqlalchemy.sql.expression.GenerativeSelect.with_for_update"><tt class="xref py py-meth docutils literal"><span class="pre">with_for_update()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect" title="sqlalchemy.sql.expression.GenerativeSelect"><tt class="xref py py-class docutils literal"><span class="pre">GenerativeSelect</span></tt></a></div>
<p>Specify a <tt class="docutils literal"><span class="pre">FOR</span> <span class="pre">UPDATE</span></tt> clause for this <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect" title="sqlalchemy.sql.expression.GenerativeSelect"><tt class="xref py py-class docutils literal"><span class="pre">GenerativeSelect</span></tt></a>.</p>
<p>E.g.:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">stmt</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">table</span><span class="p">])</span><span class="o">.</span><span class="n">with_for_update</span><span class="p">(</span><span class="n">nowait</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span></pre></div>
</div>
<p>On a database like Postgresql or Oracle, the above would render a
statement like:</p>
<div class="highlight-python"><pre>SELECT table.a, table.b FROM table FOR UPDATE NOWAIT</pre>
</div>
<p>on other backends, the <tt class="docutils literal"><span class="pre">nowait</span></tt> option is ignored and instead
would produce:</p>
<div class="highlight-python"><pre>SELECT table.a, table.b FROM table FOR UPDATE</pre>
</div>
<p>When called with no arguments, the statement will render with
the suffix <tt class="docutils literal"><span class="pre">FOR</span> <span class="pre">UPDATE</span></tt>. Additional arguments can then be
provided which allow for common database-specific
variants.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.CompoundSelect.with_for_update.params.nowait"></span><strong>nowait</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CompoundSelect.with_for_update.params.nowait">¶</a> – boolean; will render <tt class="docutils literal"><span class="pre">FOR</span> <span class="pre">UPDATE</span> <span class="pre">NOWAIT</span></tt> on Oracle
and Postgresql dialects.</li>
<li><span class="target" id="sqlalchemy.sql.expression.CompoundSelect.with_for_update.params.read"></span><strong>read</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CompoundSelect.with_for_update.params.read">¶</a> – boolean; will render <tt class="docutils literal"><span class="pre">LOCK</span> <span class="pre">IN</span> <span class="pre">SHARE</span> <span class="pre">MODE</span></tt> on MySQL,
<tt class="docutils literal"><span class="pre">FOR</span> <span class="pre">SHARE</span></tt> on Postgresql. On Postgresql, when combined with
<tt class="docutils literal"><span class="pre">nowait</span></tt>, will render <tt class="docutils literal"><span class="pre">FOR</span> <span class="pre">SHARE</span> <span class="pre">NOWAIT</span></tt>.</li>
<li><span class="target" id="sqlalchemy.sql.expression.CompoundSelect.with_for_update.params.of"></span><strong>of</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CompoundSelect.with_for_update.params.of">¶</a> – SQL expression or list of SQL expression elements
(typically <a class="reference internal" href="metadata.html#sqlalchemy.schema.Column" title="sqlalchemy.schema.Column"><tt class="xref py py-class docutils literal"><span class="pre">Column</span></tt></a> objects or a compatible expression) which
will render into a <tt class="docutils literal"><span class="pre">FOR</span> <span class="pre">UPDATE</span> <span class="pre">OF</span></tt> clause; supported by PostgreSQL
and Oracle. May render as a table or as a column depending on
backend.</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="versionadded">
<p><span>New in version 0.9.0.</span></p>
</div>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.sql.expression.CTE">
<em class="property">class </em><tt class="descclassname">sqlalchemy.sql.expression.</tt><tt class="descname">CTE</tt><big>(</big><em>selectable</em>, <em>name=None</em>, <em>recursive=False</em>, <em>_cte_alias=None</em>, <em>_restates=frozenset([])</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CTE" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <a class="reference internal" href="#sqlalchemy.sql.expression.Alias" title="sqlalchemy.sql.expression.Alias"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.sql.expression.Alias</span></tt></a></p>
<p>Represent a Common Table Expression.</p>
<p>The <a class="reference internal" href="#sqlalchemy.sql.expression.CTE" title="sqlalchemy.sql.expression.CTE"><tt class="xref py py-class docutils literal"><span class="pre">CTE</span></tt></a> object is obtained using the
<a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase.cte" title="sqlalchemy.sql.expression.SelectBase.cte"><tt class="xref py py-meth docutils literal"><span class="pre">SelectBase.cte()</span></tt></a> method from any selectable.
See that method for complete examples.</p>
<div class="versionadded">
<p><span>New in version 0.7.6.</span></p>
</div>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.CTE.c">
<tt class="descname">c</tt><a class="headerlink" href="#sqlalchemy.sql.expression.CTE.c" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.c" title="sqlalchemy.sql.expression.FromClause.c"><tt class="xref py py-attr docutils literal"><span class="pre">c</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>An alias for the <a class="reference internal" href="#sqlalchemy.sql.expression.CTE.columns" title="sqlalchemy.sql.expression.CTE.columns"><tt class="xref py py-attr docutils literal"><span class="pre">columns</span></tt></a> attribute.</p>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.CTE.columns">
<tt class="descname">columns</tt><a class="headerlink" href="#sqlalchemy.sql.expression.CTE.columns" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.columns" title="sqlalchemy.sql.expression.FromClause.columns"><tt class="xref py py-attr docutils literal"><span class="pre">columns</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>A named-based collection of <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> objects
maintained by this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<p>The <a class="reference internal" href="#sqlalchemy.sql.expression.CTE.columns" title="sqlalchemy.sql.expression.CTE.columns"><tt class="xref py py-attr docutils literal"><span class="pre">columns</span></tt></a>, or <a class="reference internal" href="#sqlalchemy.sql.expression.CTE.c" title="sqlalchemy.sql.expression.CTE.c"><tt class="xref py py-attr docutils literal"><span class="pre">c</span></tt></a> collection, is the gateway
to the construction of SQL expressions using table-bound or
other selectable-bound columns:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">select</span><span class="p">([</span><span class="n">mytable</span><span class="p">])</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="n">mytable</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">somecolumn</span> <span class="o">==</span> <span class="mi">5</span><span class="p">)</span></pre></div>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CTE.compare">
<tt class="descname">compare</tt><big>(</big><em>other</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CTE.compare" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.compare" title="sqlalchemy.sql.expression.ClauseElement.compare"><tt class="xref py py-meth docutils literal"><span class="pre">compare()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Compare this ClauseElement to the given ClauseElement.</p>
<p>Subclasses should override the default behavior, which is a
straight identity comparison.</p>
<p>**kw are arguments consumed by subclass compare() methods and
may be used to modify the criteria for comparison.
(see <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a>)</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CTE.compile">
<tt class="descname">compile</tt><big>(</big><em>bind=None</em>, <em>dialect=None</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CTE.compile" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.compile" title="sqlalchemy.sql.expression.ClauseElement.compile"><tt class="xref py py-meth docutils literal"><span class="pre">compile()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Compile this SQL expression.</p>
<p>The return value is a <a class="reference internal" href="internals.html#sqlalchemy.engine.interfaces.Compiled" title="sqlalchemy.engine.interfaces.Compiled"><tt class="xref py py-class docutils literal"><span class="pre">Compiled</span></tt></a> object.
Calling <tt class="docutils literal"><span class="pre">str()</span></tt> or <tt class="docutils literal"><span class="pre">unicode()</span></tt> on the returned value will yield a
string representation of the result. The
<a class="reference internal" href="internals.html#sqlalchemy.engine.interfaces.Compiled" title="sqlalchemy.engine.interfaces.Compiled"><tt class="xref py py-class docutils literal"><span class="pre">Compiled</span></tt></a> object also can return a
dictionary of bind parameter names and values
using the <tt class="docutils literal"><span class="pre">params</span></tt> accessor.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.CTE.compile.params.bind"></span><strong>bind</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CTE.compile.params.bind">¶</a> – An <tt class="docutils literal"><span class="pre">Engine</span></tt> or <tt class="docutils literal"><span class="pre">Connection</span></tt> from which a
<tt class="docutils literal"><span class="pre">Compiled</span></tt> will be acquired. This argument takes precedence over
this <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a>‘s bound engine, if any.</li>
<li><span class="target" id="sqlalchemy.sql.expression.CTE.compile.params.column_keys"></span><strong>column_keys</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CTE.compile.params.column_keys">¶</a> – Used for INSERT and UPDATE statements, a list of
column names which should be present in the VALUES clause of the
compiled statement. If <tt class="docutils literal"><span class="pre">None</span></tt>, all columns from the target table
object are rendered.</li>
<li><span class="target" id="sqlalchemy.sql.expression.CTE.compile.params.dialect"></span><strong>dialect</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CTE.compile.params.dialect">¶</a> – A <tt class="docutils literal"><span class="pre">Dialect</span></tt> instance from which a <tt class="docutils literal"><span class="pre">Compiled</span></tt>
will be acquired. This argument takes precedence over the <cite>bind</cite>
argument as well as this <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a>‘s bound engine,
if any.</li>
<li><span class="target" id="sqlalchemy.sql.expression.CTE.compile.params.inline"></span><strong>inline</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CTE.compile.params.inline">¶</a> – Used for INSERT statements, for a dialect which does
not support inline retrieval of newly generated primary key
columns, will force the expression used to create the new primary
key value to be rendered inline within the INSERT statement’s
VALUES clause. This typically refers to Sequence execution but may
also refer to any server-side default generation function
associated with a primary key <cite>Column</cite>.</li>
<li><span class="target" id="sqlalchemy.sql.expression.CTE.compile.params.compile_kwargs"></span><strong>compile_kwargs</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CTE.compile.params.compile_kwargs">¶</a> – <p>optional dictionary of additional parameters
that will be passed through to the compiler within all “visit”
methods. This allows any custom flag to be passed through to
a custom compilation construct, for example. It is also used
for the case of passing the <tt class="docutils literal"><span class="pre">literal_binds</span></tt> flag through:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy.sql</span> <span class="kn">import</span> <span class="n">table</span><span class="p">,</span> <span class="n">column</span><span class="p">,</span> <span class="n">select</span>
<span class="n">t</span> <span class="o">=</span> <span class="n">table</span><span class="p">(</span><span class="s">'t'</span><span class="p">,</span> <span class="n">column</span><span class="p">(</span><span class="s">'x'</span><span class="p">))</span>
<span class="n">s</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">t</span><span class="p">])</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="n">t</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">x</span> <span class="o">==</span> <span class="mi">5</span><span class="p">)</span>
<span class="k">print</span> <span class="n">s</span><span class="o">.</span><span class="n">compile</span><span class="p">(</span><span class="n">compile_kwargs</span><span class="o">=</span><span class="p">{</span><span class="s">"literal_binds"</span><span class="p">:</span> <span class="bp">True</span><span class="p">})</span></pre></div>
</div>
<div class="versionadded">
<p><span>New in version 0.9.0.</span></p>
</div>
</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="../faq.html#faq-sql-expression-string"><em>How do I render SQL expressions as strings, possibly with bound parameters inlined?</em></a></p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CTE.correspond_on_equivalents">
<tt class="descname">correspond_on_equivalents</tt><big>(</big><em>column</em>, <em>equivalents</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CTE.correspond_on_equivalents" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.correspond_on_equivalents" title="sqlalchemy.sql.expression.FromClause.correspond_on_equivalents"><tt class="xref py py-meth docutils literal"><span class="pre">correspond_on_equivalents()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return corresponding_column for the given column, or if None
search for a match in the given dictionary.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CTE.corresponding_column">
<tt class="descname">corresponding_column</tt><big>(</big><em>column</em>, <em>require_embedded=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CTE.corresponding_column" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.corresponding_column" title="sqlalchemy.sql.expression.FromClause.corresponding_column"><tt class="xref py py-meth docutils literal"><span class="pre">corresponding_column()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Given a <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a>, return the exported
<a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> object from this <a class="reference internal" href="#sqlalchemy.sql.expression.Selectable" title="sqlalchemy.sql.expression.Selectable"><tt class="xref py py-class docutils literal"><span class="pre">Selectable</span></tt></a>
which corresponds to that original
<a class="reference internal" href="metadata.html#sqlalchemy.schema.Column" title="sqlalchemy.schema.Column"><tt class="xref py py-class docutils literal"><span class="pre">Column</span></tt></a> via a common ancestor
column.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.CTE.corresponding_column.params.column"></span><strong>column</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CTE.corresponding_column.params.column">¶</a> – the target <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> to be matched</li>
<li><span class="target" id="sqlalchemy.sql.expression.CTE.corresponding_column.params.require_embedded"></span><strong>require_embedded</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CTE.corresponding_column.params.require_embedded">¶</a> – only return corresponding columns for
the given <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a>, if the given
<a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> is actually present within a sub-element
of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>. Normally the column will match if
it merely shares a common ancestor with one of the exported
columns of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CTE.count">
<tt class="descname">count</tt><big>(</big><em>whereclause=None</em>, <em>**params</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CTE.count" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.count" title="sqlalchemy.sql.expression.FromClause.count"><tt class="xref py py-meth docutils literal"><span class="pre">count()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>return a SELECT COUNT generated against this
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.CTE.foreign_keys">
<tt class="descname">foreign_keys</tt><a class="headerlink" href="#sqlalchemy.sql.expression.CTE.foreign_keys" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.foreign_keys" title="sqlalchemy.sql.expression.FromClause.foreign_keys"><tt class="xref py py-attr docutils literal"><span class="pre">foreign_keys</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return the collection of ForeignKey objects which this
FromClause references.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CTE.join">
<tt class="descname">join</tt><big>(</big><em>right</em>, <em>onclause=None</em>, <em>isouter=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CTE.join" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">join()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return a <a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> from this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>
to another <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<p>E.g.:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="n">join</span>
<span class="n">j</span> <span class="o">=</span> <span class="n">user_table</span><span class="o">.</span><span class="n">join</span><span class="p">(</span><span class="n">address_table</span><span class="p">,</span>
<span class="n">user_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span> <span class="o">==</span> <span class="n">address_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">user_id</span><span class="p">)</span>
<span class="n">stmt</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">user_table</span><span class="p">])</span><span class="o">.</span><span class="n">select_from</span><span class="p">(</span><span class="n">j</span><span class="p">)</span></pre></div>
</div>
<p>would emit SQL along the lines of:</p>
<div class="highlight-python"><pre>SELECT user.id, user.name FROM user
JOIN address ON user.id = address.user_id</pre>
</div>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.CTE.join.params.right"></span><strong>right</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CTE.join.params.right">¶</a> – the right side of the join; this is any
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> object such as a <a class="reference internal" href="metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a> object, and
may also be a selectable-compatible object such as an ORM-mapped
class.</li>
<li><span class="target" id="sqlalchemy.sql.expression.CTE.join.params.onclause"></span><strong>onclause</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CTE.join.params.onclause">¶</a> – a SQL expression representing the ON clause of the
join. If left at <tt class="docutils literal"><span class="pre">None</span></tt>, <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a> will attempt to
join the two tables based on a foreign key relationship.</li>
<li><span class="target" id="sqlalchemy.sql.expression.CTE.join.params.isouter"></span><strong>isouter</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CTE.join.params.isouter">¶</a> – if True, render a LEFT OUTER JOIN, instead of JOIN.</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p><a class="reference internal" href="#sqlalchemy.sql.expression.join" title="sqlalchemy.sql.expression.join"><tt class="xref py py-func docutils literal"><span class="pre">join()</span></tt></a> - standalone function</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> - the type of object produced</p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CTE.outerjoin">
<tt class="descname">outerjoin</tt><big>(</big><em>right</em>, <em>onclause=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CTE.outerjoin" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.outerjoin" title="sqlalchemy.sql.expression.FromClause.outerjoin"><tt class="xref py py-meth docutils literal"><span class="pre">outerjoin()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return a <a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> from this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>
to another <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>, with the “isouter” flag set to
True.</p>
<p>E.g.:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="n">outerjoin</span>
<span class="n">j</span> <span class="o">=</span> <span class="n">user_table</span><span class="o">.</span><span class="n">outerjoin</span><span class="p">(</span><span class="n">address_table</span><span class="p">,</span>
<span class="n">user_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span> <span class="o">==</span> <span class="n">address_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">user_id</span><span class="p">)</span></pre></div>
</div>
<p>The above is equivalent to:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">j</span> <span class="o">=</span> <span class="n">user_table</span><span class="o">.</span><span class="n">join</span><span class="p">(</span>
<span class="n">address_table</span><span class="p">,</span>
<span class="n">user_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span> <span class="o">==</span> <span class="n">address_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">user_id</span><span class="p">,</span>
<span class="n">isouter</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span></pre></div>
</div>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.CTE.outerjoin.params.right"></span><strong>right</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CTE.outerjoin.params.right">¶</a> – the right side of the join; this is any
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> object such as a <a class="reference internal" href="metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a> object, and
may also be a selectable-compatible object such as an ORM-mapped
class.</li>
<li><span class="target" id="sqlalchemy.sql.expression.CTE.outerjoin.params.onclause"></span><strong>onclause</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.CTE.outerjoin.params.onclause">¶</a> – a SQL expression representing the ON clause of the
join. If left at <tt class="docutils literal"><span class="pre">None</span></tt>, <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a> will attempt to
join the two tables based on a foreign key relationship.</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p><a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a></p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a></p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CTE.params">
<tt class="descname">params</tt><big>(</big><em>*optionaldict</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CTE.params" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.params" title="sqlalchemy.sql.expression.ClauseElement.params"><tt class="xref py py-meth docutils literal"><span class="pre">params()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Return a copy with <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.bindparam" title="sqlalchemy.sql.expression.bindparam"><tt class="xref py py-func docutils literal"><span class="pre">bindparam()</span></tt></a> elements replaced.</p>
<p>Returns a copy of this ClauseElement with <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.bindparam" title="sqlalchemy.sql.expression.bindparam"><tt class="xref py py-func docutils literal"><span class="pre">bindparam()</span></tt></a>
elements replaced with values taken from the given dictionary:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="n">clause</span> <span class="o">=</span> <span class="n">column</span><span class="p">(</span><span class="s">'x'</span><span class="p">)</span> <span class="o">+</span> <span class="n">bindparam</span><span class="p">(</span><span class="s">'foo'</span><span class="p">)</span>
<span class="gp">>>> </span><span class="k">print</span> <span class="n">clause</span><span class="o">.</span><span class="n">compile</span><span class="p">()</span><span class="o">.</span><span class="n">params</span>
<span class="go">{'foo':None}</span>
<span class="gp">>>> </span><span class="k">print</span> <span class="n">clause</span><span class="o">.</span><span class="n">params</span><span class="p">({</span><span class="s">'foo'</span><span class="p">:</span><span class="mi">7</span><span class="p">})</span><span class="o">.</span><span class="n">compile</span><span class="p">()</span><span class="o">.</span><span class="n">params</span>
<span class="go">{'foo':7}</span></pre></div>
</div>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.CTE.primary_key">
<tt class="descname">primary_key</tt><a class="headerlink" href="#sqlalchemy.sql.expression.CTE.primary_key" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.primary_key" title="sqlalchemy.sql.expression.FromClause.primary_key"><tt class="xref py py-attr docutils literal"><span class="pre">primary_key</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return the collection of Column objects which comprise the
primary key of this FromClause.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CTE.replace_selectable">
<tt class="descname">replace_selectable</tt><big>(</big><em>old</em>, <em>alias</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CTE.replace_selectable" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.replace_selectable" title="sqlalchemy.sql.expression.FromClause.replace_selectable"><tt class="xref py py-meth docutils literal"><span class="pre">replace_selectable()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>replace all occurrences of FromClause ‘old’ with the given Alias
object, returning a copy of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CTE.select">
<tt class="descname">select</tt><big>(</big><em>whereclause=None</em>, <em>**params</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CTE.select" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.select" title="sqlalchemy.sql.expression.FromClause.select"><tt class="xref py py-meth docutils literal"><span class="pre">select()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>return a SELECT of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a> - general purpose
method which allows for arbitrary column lists.</p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CTE.self_group">
<tt class="descname">self_group</tt><big>(</big><em>against=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CTE.self_group" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.self_group" title="sqlalchemy.sql.expression.ClauseElement.self_group"><tt class="xref py py-meth docutils literal"><span class="pre">self_group()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Apply a ‘grouping’ to this <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a>.</p>
<p>This method is overridden by subclasses to return a
“grouping” construct, i.e. parenthesis. In particular
it’s used by “binary” expressions to provide a grouping
around themselves when placed into a larger expression,
as well as by <a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a> constructs when placed into
the FROM clause of another <a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a>. (Note that
subqueries should be normally created using the
<a class="reference internal" href="#sqlalchemy.sql.expression.Select.alias" title="sqlalchemy.sql.expression.Select.alias"><tt class="xref py py-meth docutils literal"><span class="pre">Select.alias()</span></tt></a> method, as many platforms require
nested SELECT statements to be named).</p>
<p>As expressions are composed together, the application of
<a class="reference internal" href="#sqlalchemy.sql.expression.CTE.self_group" title="sqlalchemy.sql.expression.CTE.self_group"><tt class="xref py py-meth docutils literal"><span class="pre">self_group()</span></tt></a> is automatic - end-user code should never
need to use this method directly. Note that SQLAlchemy’s
clause constructs take operator precedence into account -
so parenthesis might not be needed, for example, in
an expression like <tt class="docutils literal"><span class="pre">x</span> <span class="pre">OR</span> <span class="pre">(y</span> <span class="pre">AND</span> <span class="pre">z)</span></tt> - AND takes precedence
over OR.</p>
<p>The base <a class="reference internal" href="#sqlalchemy.sql.expression.CTE.self_group" title="sqlalchemy.sql.expression.CTE.self_group"><tt class="xref py py-meth docutils literal"><span class="pre">self_group()</span></tt></a> method of <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a>
just returns self.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.CTE.unique_params">
<tt class="descname">unique_params</tt><big>(</big><em>*optionaldict</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.CTE.unique_params" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.unique_params" title="sqlalchemy.sql.expression.ClauseElement.unique_params"><tt class="xref py py-meth docutils literal"><span class="pre">unique_params()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Return a copy with <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.bindparam" title="sqlalchemy.sql.expression.bindparam"><tt class="xref py py-func docutils literal"><span class="pre">bindparam()</span></tt></a> elements replaced.</p>
<p>Same functionality as <tt class="docutils literal"><span class="pre">params()</span></tt>, except adds <cite>unique=True</cite>
to affected bind parameters so that multiple statements can be
used.</p>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.sql.expression.Executable">
<em class="property">class </em><tt class="descclassname">sqlalchemy.sql.expression.</tt><tt class="descname">Executable</tt><a class="headerlink" href="#sqlalchemy.sql.expression.Executable" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.sql.expression.Generative</span></tt></p>
<p>Mark a ClauseElement as supporting execution.</p>
<p><a class="reference internal" href="#sqlalchemy.sql.expression.Executable" title="sqlalchemy.sql.expression.Executable"><tt class="xref py py-class docutils literal"><span class="pre">Executable</span></tt></a> is a superclass for all “statement” types
of objects, including <a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a>, <a class="reference internal" href="dml.html#sqlalchemy.sql.expression.delete" title="sqlalchemy.sql.expression.delete"><tt class="xref py py-func docutils literal"><span class="pre">delete()</span></tt></a>, <a class="reference internal" href="dml.html#sqlalchemy.sql.expression.update" title="sqlalchemy.sql.expression.update"><tt class="xref py py-func docutils literal"><span class="pre">update()</span></tt></a>,
<a class="reference internal" href="dml.html#sqlalchemy.sql.expression.insert" title="sqlalchemy.sql.expression.insert"><tt class="xref py py-func docutils literal"><span class="pre">insert()</span></tt></a>, <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.text" title="sqlalchemy.sql.expression.text"><tt class="xref py py-func docutils literal"><span class="pre">text()</span></tt></a>.</p>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.Executable.bind">
<tt class="descname">bind</tt><a class="headerlink" href="#sqlalchemy.sql.expression.Executable.bind" title="Permalink to this definition">¶</a></dt>
<dd><p>Returns the <a class="reference internal" href="connections.html#sqlalchemy.engine.Engine" title="sqlalchemy.engine.Engine"><tt class="xref py py-class docutils literal"><span class="pre">Engine</span></tt></a> or <a class="reference internal" href="connections.html#sqlalchemy.engine.Connection" title="sqlalchemy.engine.Connection"><tt class="xref py py-class docutils literal"><span class="pre">Connection</span></tt></a> to
which this <a class="reference internal" href="#sqlalchemy.sql.expression.Executable" title="sqlalchemy.sql.expression.Executable"><tt class="xref py py-class docutils literal"><span class="pre">Executable</span></tt></a> is bound, or None if none found.</p>
<p>This is a traversal which checks locally, then
checks among the “from” clauses of associated objects
until a bound engine or connection is found.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Executable.execute">
<tt class="descname">execute</tt><big>(</big><em>*multiparams</em>, <em>**params</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Executable.execute" title="Permalink to this definition">¶</a></dt>
<dd><p>Compile and execute this <a class="reference internal" href="#sqlalchemy.sql.expression.Executable" title="sqlalchemy.sql.expression.Executable"><tt class="xref py py-class docutils literal"><span class="pre">Executable</span></tt></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Executable.execution_options">
<tt class="descname">execution_options</tt><big>(</big><em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Executable.execution_options" title="Permalink to this definition">¶</a></dt>
<dd><p>Set non-SQL options for the statement which take effect during
execution.</p>
<p>Execution options can be set on a per-statement or
per <a class="reference internal" href="connections.html#sqlalchemy.engine.Connection" title="sqlalchemy.engine.Connection"><tt class="xref py py-class docutils literal"><span class="pre">Connection</span></tt></a> basis. Additionally, the
<a class="reference internal" href="connections.html#sqlalchemy.engine.Engine" title="sqlalchemy.engine.Engine"><tt class="xref py py-class docutils literal"><span class="pre">Engine</span></tt></a> and ORM <a class="reference internal" href="../orm/query.html#sqlalchemy.orm.query.Query" title="sqlalchemy.orm.query.Query"><tt class="xref py py-class docutils literal"><span class="pre">Query</span></tt></a> objects provide
access to execution options which they in turn configure upon
connections.</p>
<p>The <a class="reference internal" href="#sqlalchemy.sql.expression.Executable.execution_options" title="sqlalchemy.sql.expression.Executable.execution_options"><tt class="xref py py-meth docutils literal"><span class="pre">execution_options()</span></tt></a> method is generative. A new
instance of this statement is returned that contains the options:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">statement</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">x</span><span class="p">,</span> <span class="n">table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">y</span><span class="p">])</span>
<span class="n">statement</span> <span class="o">=</span> <span class="n">statement</span><span class="o">.</span><span class="n">execution_options</span><span class="p">(</span><span class="n">autocommit</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span></pre></div>
</div>
<p>Note that only a subset of possible execution options can be applied
to a statement - these include “autocommit” and “stream_results”,
but not “isolation_level” or “compiled_cache”.
See <a class="reference internal" href="connections.html#sqlalchemy.engine.Connection.execution_options" title="sqlalchemy.engine.Connection.execution_options"><tt class="xref py py-meth docutils literal"><span class="pre">Connection.execution_options()</span></tt></a> for a full list of
possible options.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p><a class="reference internal" href="connections.html#sqlalchemy.engine.Connection.execution_options" title="sqlalchemy.engine.Connection.execution_options"><tt class="xref py py-meth docutils literal"><span class="pre">Connection.execution_options()</span></tt></a></p>
<p class="last"><a class="reference internal" href="../orm/query.html#sqlalchemy.orm.query.Query.execution_options" title="sqlalchemy.orm.query.Query.execution_options"><tt class="xref py py-meth docutils literal"><span class="pre">Query.execution_options()</span></tt></a></p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Executable.scalar">
<tt class="descname">scalar</tt><big>(</big><em>*multiparams</em>, <em>**params</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Executable.scalar" title="Permalink to this definition">¶</a></dt>
<dd><p>Compile and execute this <a class="reference internal" href="#sqlalchemy.sql.expression.Executable" title="sqlalchemy.sql.expression.Executable"><tt class="xref py py-class docutils literal"><span class="pre">Executable</span></tt></a>, returning the
result’s scalar representation.</p>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.sql.expression.FromClause">
<em class="property">class </em><tt class="descclassname">sqlalchemy.sql.expression.</tt><tt class="descname">FromClause</tt><a class="headerlink" href="#sqlalchemy.sql.expression.FromClause" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <a class="reference internal" href="#sqlalchemy.sql.expression.Selectable" title="sqlalchemy.sql.expression.Selectable"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.sql.expression.Selectable</span></tt></a></p>
<p>Represent an element that can be used within the <tt class="docutils literal"><span class="pre">FROM</span></tt>
clause of a <tt class="docutils literal"><span class="pre">SELECT</span></tt> statement.</p>
<p>The most common forms of <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> are the
<a class="reference internal" href="metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a> and the <a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a> constructs. Key
features common to all <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> objects include:</p>
<ul class="simple">
<li>a <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.c" title="sqlalchemy.sql.expression.FromClause.c"><tt class="xref py py-attr docutils literal"><span class="pre">c</span></tt></a> collection, which provides per-name access to a collection
of <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> objects.</li>
<li>a <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.primary_key" title="sqlalchemy.sql.expression.FromClause.primary_key"><tt class="xref py py-attr docutils literal"><span class="pre">primary_key</span></tt></a> attribute, which is a collection of all those
<a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> objects that indicate the <tt class="docutils literal"><span class="pre">primary_key</span></tt> flag.</li>
<li>Methods to generate various derivations of a “from” clause, including
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.alias" title="sqlalchemy.sql.expression.FromClause.alias"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.alias()</span></tt></a>, <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a>,
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.select" title="sqlalchemy.sql.expression.FromClause.select"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.select()</span></tt></a>.</li>
</ul>
<dl class="method">
<dt id="sqlalchemy.sql.expression.FromClause.alias">
<tt class="descname">alias</tt><big>(</big><em>name=None</em>, <em>flat=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.FromClause.alias" title="Permalink to this definition">¶</a></dt>
<dd><p>return an alias of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<p>This is shorthand for calling:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="n">alias</span>
<span class="n">a</span> <span class="o">=</span> <span class="n">alias</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">name</span><span class="o">=</span><span class="n">name</span><span class="p">)</span></pre></div>
</div>
<p>See <a class="reference internal" href="#sqlalchemy.sql.expression.alias" title="sqlalchemy.sql.expression.alias"><tt class="xref py py-func docutils literal"><span class="pre">alias()</span></tt></a> for details.</p>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.FromClause.c">
<tt class="descname">c</tt><a class="headerlink" href="#sqlalchemy.sql.expression.FromClause.c" title="Permalink to this definition">¶</a></dt>
<dd><p>An alias for the <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.columns" title="sqlalchemy.sql.expression.FromClause.columns"><tt class="xref py py-attr docutils literal"><span class="pre">columns</span></tt></a> attribute.</p>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.FromClause.columns">
<tt class="descname">columns</tt><a class="headerlink" href="#sqlalchemy.sql.expression.FromClause.columns" title="Permalink to this definition">¶</a></dt>
<dd><p>A named-based collection of <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> objects
maintained by this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<p>The <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.columns" title="sqlalchemy.sql.expression.FromClause.columns"><tt class="xref py py-attr docutils literal"><span class="pre">columns</span></tt></a>, or <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.c" title="sqlalchemy.sql.expression.FromClause.c"><tt class="xref py py-attr docutils literal"><span class="pre">c</span></tt></a> collection, is the gateway
to the construction of SQL expressions using table-bound or
other selectable-bound columns:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">select</span><span class="p">([</span><span class="n">mytable</span><span class="p">])</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="n">mytable</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">somecolumn</span> <span class="o">==</span> <span class="mi">5</span><span class="p">)</span></pre></div>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.FromClause.correspond_on_equivalents">
<tt class="descname">correspond_on_equivalents</tt><big>(</big><em>column</em>, <em>equivalents</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.FromClause.correspond_on_equivalents" title="Permalink to this definition">¶</a></dt>
<dd><p>Return corresponding_column for the given column, or if None
search for a match in the given dictionary.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.FromClause.corresponding_column">
<tt class="descname">corresponding_column</tt><big>(</big><em>column</em>, <em>require_embedded=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.FromClause.corresponding_column" title="Permalink to this definition">¶</a></dt>
<dd><p>Given a <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a>, return the exported
<a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> object from this <a class="reference internal" href="#sqlalchemy.sql.expression.Selectable" title="sqlalchemy.sql.expression.Selectable"><tt class="xref py py-class docutils literal"><span class="pre">Selectable</span></tt></a>
which corresponds to that original
<a class="reference internal" href="metadata.html#sqlalchemy.schema.Column" title="sqlalchemy.schema.Column"><tt class="xref py py-class docutils literal"><span class="pre">Column</span></tt></a> via a common ancestor
column.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.FromClause.corresponding_column.params.column"></span><strong>column</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.FromClause.corresponding_column.params.column">¶</a> – the target <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> to be matched</li>
<li><span class="target" id="sqlalchemy.sql.expression.FromClause.corresponding_column.params.require_embedded"></span><strong>require_embedded</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.FromClause.corresponding_column.params.require_embedded">¶</a> – only return corresponding columns for
the given <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a>, if the given
<a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> is actually present within a sub-element
of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>. Normally the column will match if
it merely shares a common ancestor with one of the exported
columns of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.FromClause.count">
<tt class="descname">count</tt><big>(</big><em>whereclause=None</em>, <em>**params</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.FromClause.count" title="Permalink to this definition">¶</a></dt>
<dd><p>return a SELECT COUNT generated against this
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.FromClause.description">
<tt class="descname">description</tt><a class="headerlink" href="#sqlalchemy.sql.expression.FromClause.description" title="Permalink to this definition">¶</a></dt>
<dd><p>a brief description of this FromClause.</p>
<p>Used primarily for error message formatting.</p>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.FromClause.foreign_keys">
<tt class="descname">foreign_keys</tt><a class="headerlink" href="#sqlalchemy.sql.expression.FromClause.foreign_keys" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the collection of ForeignKey objects which this
FromClause references.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.FromClause.is_derived_from">
<tt class="descname">is_derived_from</tt><big>(</big><em>fromclause</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.FromClause.is_derived_from" title="Permalink to this definition">¶</a></dt>
<dd><p>Return True if this FromClause is ‘derived’ from the given
FromClause.</p>
<p>An example would be an Alias of a Table is derived from that Table.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.FromClause.join">
<tt class="descname">join</tt><big>(</big><em>right</em>, <em>onclause=None</em>, <em>isouter=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.FromClause.join" title="Permalink to this definition">¶</a></dt>
<dd><p>Return a <a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> from this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>
to another <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<p>E.g.:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="n">join</span>
<span class="n">j</span> <span class="o">=</span> <span class="n">user_table</span><span class="o">.</span><span class="n">join</span><span class="p">(</span><span class="n">address_table</span><span class="p">,</span>
<span class="n">user_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span> <span class="o">==</span> <span class="n">address_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">user_id</span><span class="p">)</span>
<span class="n">stmt</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">user_table</span><span class="p">])</span><span class="o">.</span><span class="n">select_from</span><span class="p">(</span><span class="n">j</span><span class="p">)</span></pre></div>
</div>
<p>would emit SQL along the lines of:</p>
<div class="highlight-python"><pre>SELECT user.id, user.name FROM user
JOIN address ON user.id = address.user_id</pre>
</div>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.FromClause.join.params.right"></span><strong>right</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.FromClause.join.params.right">¶</a> – the right side of the join; this is any
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> object such as a <a class="reference internal" href="metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a> object, and
may also be a selectable-compatible object such as an ORM-mapped
class.</li>
<li><span class="target" id="sqlalchemy.sql.expression.FromClause.join.params.onclause"></span><strong>onclause</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.FromClause.join.params.onclause">¶</a> – a SQL expression representing the ON clause of the
join. If left at <tt class="docutils literal"><span class="pre">None</span></tt>, <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a> will attempt to
join the two tables based on a foreign key relationship.</li>
<li><span class="target" id="sqlalchemy.sql.expression.FromClause.join.params.isouter"></span><strong>isouter</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.FromClause.join.params.isouter">¶</a> – if True, render a LEFT OUTER JOIN, instead of JOIN.</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p><a class="reference internal" href="#sqlalchemy.sql.expression.join" title="sqlalchemy.sql.expression.join"><tt class="xref py py-func docutils literal"><span class="pre">join()</span></tt></a> - standalone function</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> - the type of object produced</p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.FromClause.outerjoin">
<tt class="descname">outerjoin</tt><big>(</big><em>right</em>, <em>onclause=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.FromClause.outerjoin" title="Permalink to this definition">¶</a></dt>
<dd><p>Return a <a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> from this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>
to another <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>, with the “isouter” flag set to
True.</p>
<p>E.g.:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="n">outerjoin</span>
<span class="n">j</span> <span class="o">=</span> <span class="n">user_table</span><span class="o">.</span><span class="n">outerjoin</span><span class="p">(</span><span class="n">address_table</span><span class="p">,</span>
<span class="n">user_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span> <span class="o">==</span> <span class="n">address_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">user_id</span><span class="p">)</span></pre></div>
</div>
<p>The above is equivalent to:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">j</span> <span class="o">=</span> <span class="n">user_table</span><span class="o">.</span><span class="n">join</span><span class="p">(</span>
<span class="n">address_table</span><span class="p">,</span>
<span class="n">user_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span> <span class="o">==</span> <span class="n">address_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">user_id</span><span class="p">,</span>
<span class="n">isouter</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span></pre></div>
</div>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.FromClause.outerjoin.params.right"></span><strong>right</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.FromClause.outerjoin.params.right">¶</a> – the right side of the join; this is any
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> object such as a <a class="reference internal" href="metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a> object, and
may also be a selectable-compatible object such as an ORM-mapped
class.</li>
<li><span class="target" id="sqlalchemy.sql.expression.FromClause.outerjoin.params.onclause"></span><strong>onclause</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.FromClause.outerjoin.params.onclause">¶</a> – a SQL expression representing the ON clause of the
join. If left at <tt class="docutils literal"><span class="pre">None</span></tt>, <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a> will attempt to
join the two tables based on a foreign key relationship.</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p><a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a></p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a></p>
</div>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.FromClause.primary_key">
<tt class="descname">primary_key</tt><a class="headerlink" href="#sqlalchemy.sql.expression.FromClause.primary_key" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the collection of Column objects which comprise the
primary key of this FromClause.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.FromClause.replace_selectable">
<tt class="descname">replace_selectable</tt><big>(</big><em>old</em>, <em>alias</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.FromClause.replace_selectable" title="Permalink to this definition">¶</a></dt>
<dd><p>replace all occurrences of FromClause ‘old’ with the given Alias
object, returning a copy of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.FromClause.schema">
<tt class="descname">schema</tt><em class="property"> = None</em><a class="headerlink" href="#sqlalchemy.sql.expression.FromClause.schema" title="Permalink to this definition">¶</a></dt>
<dd><p>Define the ‘schema’ attribute for this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<p>This is typically <tt class="docutils literal"><span class="pre">None</span></tt> for most objects except that of
<a class="reference internal" href="metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a>, where it is taken as the value of the
<a class="reference internal" href="metadata.html#sqlalchemy.schema.Table.params.schema" title="sqlalchemy.schema.Table"><tt class="xref py py-paramref docutils literal"><span class="pre">Table.schema</span></tt></a> argument.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.FromClause.select">
<tt class="descname">select</tt><big>(</big><em>whereclause=None</em>, <em>**params</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.FromClause.select" title="Permalink to this definition">¶</a></dt>
<dd><p>return a SELECT of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a> - general purpose
method which allows for arbitrary column lists.</p>
</div>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.sql.expression.GenerativeSelect">
<em class="property">class </em><tt class="descclassname">sqlalchemy.sql.expression.</tt><tt class="descname">GenerativeSelect</tt><big>(</big><em>use_labels=False</em>, <em>for_update=False</em>, <em>limit=None</em>, <em>offset=None</em>, <em>order_by=None</em>, <em>group_by=None</em>, <em>bind=None</em>, <em>autocommit=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase" title="sqlalchemy.sql.expression.SelectBase"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.sql.expression.SelectBase</span></tt></a></p>
<p>Base class for SELECT statements where additional elements can be
added.</p>
<p>This serves as the base for <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> and <a class="reference internal" href="#sqlalchemy.sql.expression.CompoundSelect" title="sqlalchemy.sql.expression.CompoundSelect"><tt class="xref py py-class docutils literal"><span class="pre">CompoundSelect</span></tt></a>
where elements such as ORDER BY, GROUP BY can be added and column
rendering can be controlled. Compare to <a class="reference internal" href="#sqlalchemy.sql.expression.TextAsFrom" title="sqlalchemy.sql.expression.TextAsFrom"><tt class="xref py py-class docutils literal"><span class="pre">TextAsFrom</span></tt></a>, which,
while it subclasses <a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase" title="sqlalchemy.sql.expression.SelectBase"><tt class="xref py py-class docutils literal"><span class="pre">SelectBase</span></tt></a> and is also a SELECT construct,
represents a fixed textual string which cannot be altered at this level,
only wrapped as a subquery.</p>
<div class="versionadded">
<p><span>New in version 0.9.0: </span><a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect" title="sqlalchemy.sql.expression.GenerativeSelect"><tt class="xref py py-class docutils literal"><span class="pre">GenerativeSelect</span></tt></a> was added to
provide functionality specific to <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> and
<a class="reference internal" href="#sqlalchemy.sql.expression.CompoundSelect" title="sqlalchemy.sql.expression.CompoundSelect"><tt class="xref py py-class docutils literal"><span class="pre">CompoundSelect</span></tt></a> while allowing <a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase" title="sqlalchemy.sql.expression.SelectBase"><tt class="xref py py-class docutils literal"><span class="pre">SelectBase</span></tt></a> to be
used for other SELECT-like objects, e.g. <a class="reference internal" href="#sqlalchemy.sql.expression.TextAsFrom" title="sqlalchemy.sql.expression.TextAsFrom"><tt class="xref py py-class docutils literal"><span class="pre">TextAsFrom</span></tt></a>.</p>
</div>
<dl class="method">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.alias">
<tt class="descname">alias</tt><big>(</big><em>name=None</em>, <em>flat=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.alias" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.alias" title="sqlalchemy.sql.expression.FromClause.alias"><tt class="xref py py-meth docutils literal"><span class="pre">alias()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>return an alias of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<p>This is shorthand for calling:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="n">alias</span>
<span class="n">a</span> <span class="o">=</span> <span class="n">alias</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">name</span><span class="o">=</span><span class="n">name</span><span class="p">)</span></pre></div>
</div>
<p>See <a class="reference internal" href="#sqlalchemy.sql.expression.alias" title="sqlalchemy.sql.expression.alias"><tt class="xref py py-func docutils literal"><span class="pre">alias()</span></tt></a> for details.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.append_group_by">
<tt class="descname">append_group_by</tt><big>(</big><em>*clauses</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.append_group_by" title="Permalink to this definition">¶</a></dt>
<dd><p>Append the given GROUP BY criterion applied to this selectable.</p>
<p>The criterion will be appended to any pre-existing GROUP BY criterion.</p>
<p>This is an <strong>in-place</strong> mutation method; the
<a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.group_by" title="sqlalchemy.sql.expression.GenerativeSelect.group_by"><tt class="xref py py-meth docutils literal"><span class="pre">group_by()</span></tt></a> method is preferred, as it
provides standard <a class="reference internal" href="../glossary.html#term-method-chaining"><em class="xref std std-term">method chaining</em></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.append_order_by">
<tt class="descname">append_order_by</tt><big>(</big><em>*clauses</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.append_order_by" title="Permalink to this definition">¶</a></dt>
<dd><p>Append the given ORDER BY criterion applied to this selectable.</p>
<p>The criterion will be appended to any pre-existing ORDER BY criterion.</p>
<p>This is an <strong>in-place</strong> mutation method; the
<a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.order_by" title="sqlalchemy.sql.expression.GenerativeSelect.order_by"><tt class="xref py py-meth docutils literal"><span class="pre">order_by()</span></tt></a> method is preferred, as it
provides standard <a class="reference internal" href="../glossary.html#term-method-chaining"><em class="xref std std-term">method chaining</em></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.apply_labels">
<tt class="descname">apply_labels</tt><big>(</big><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.apply_labels" title="Permalink to this definition">¶</a></dt>
<dd><p>return a new selectable with the ‘use_labels’ flag set to True.</p>
<p>This will result in column expressions being generated using labels
against their table name, such as “SELECT somecolumn AS
tablename_somecolumn”. This allows selectables which contain multiple
FROM clauses to produce a unique set of column names regardless of
name conflicts among the individual FROM clauses.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.as_scalar">
<tt class="descname">as_scalar</tt><big>(</big><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.as_scalar" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase.as_scalar" title="sqlalchemy.sql.expression.SelectBase.as_scalar"><tt class="xref py py-meth docutils literal"><span class="pre">as_scalar()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase" title="sqlalchemy.sql.expression.SelectBase"><tt class="xref py py-class docutils literal"><span class="pre">SelectBase</span></tt></a></div>
<p>return a ‘scalar’ representation of this selectable, which can be
used as a column expression.</p>
<p>Typically, a select statement which has only one column in its columns
clause is eligible to be used as a scalar expression.</p>
<p>The returned object is an instance of
<a class="reference internal" href="#sqlalchemy.sql.expression.ScalarSelect" title="sqlalchemy.sql.expression.ScalarSelect"><tt class="xref py py-class docutils literal"><span class="pre">ScalarSelect</span></tt></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.autocommit">
<tt class="descname">autocommit</tt><big>(</big><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.autocommit" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase.autocommit" title="sqlalchemy.sql.expression.SelectBase.autocommit"><tt class="xref py py-meth docutils literal"><span class="pre">autocommit()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase" title="sqlalchemy.sql.expression.SelectBase"><tt class="xref py py-class docutils literal"><span class="pre">SelectBase</span></tt></a></div>
<p>return a new selectable with the ‘autocommit’ flag set to
True.</p>
<div class="deprecated">
<p><span>Deprecated since version 0.6: </span><tt class="docutils literal"><span class="pre">autocommit()</span></tt> is deprecated. Use <a class="reference internal" href="#sqlalchemy.sql.expression.Executable.execution_options" title="sqlalchemy.sql.expression.Executable.execution_options"><tt class="xref py py-meth docutils literal"><span class="pre">Executable.execution_options()</span></tt></a> with the ‘autocommit’ flag.</p>
</div>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.bind">
<tt class="descname">bind</tt><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.bind" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.Executable.bind" title="sqlalchemy.sql.expression.Executable.bind"><tt class="xref py py-attr docutils literal"><span class="pre">bind</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.Executable" title="sqlalchemy.sql.expression.Executable"><tt class="xref py py-class docutils literal"><span class="pre">Executable</span></tt></a></div>
<p>Returns the <a class="reference internal" href="connections.html#sqlalchemy.engine.Engine" title="sqlalchemy.engine.Engine"><tt class="xref py py-class docutils literal"><span class="pre">Engine</span></tt></a> or <a class="reference internal" href="connections.html#sqlalchemy.engine.Connection" title="sqlalchemy.engine.Connection"><tt class="xref py py-class docutils literal"><span class="pre">Connection</span></tt></a> to
which this <a class="reference internal" href="#sqlalchemy.sql.expression.Executable" title="sqlalchemy.sql.expression.Executable"><tt class="xref py py-class docutils literal"><span class="pre">Executable</span></tt></a> is bound, or None if none found.</p>
<p>This is a traversal which checks locally, then
checks among the “from” clauses of associated objects
until a bound engine or connection is found.</p>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.c">
<tt class="descname">c</tt><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.c" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.c" title="sqlalchemy.sql.expression.FromClause.c"><tt class="xref py py-attr docutils literal"><span class="pre">c</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>An alias for the <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.columns" title="sqlalchemy.sql.expression.GenerativeSelect.columns"><tt class="xref py py-attr docutils literal"><span class="pre">columns</span></tt></a> attribute.</p>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.columns">
<tt class="descname">columns</tt><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.columns" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.columns" title="sqlalchemy.sql.expression.FromClause.columns"><tt class="xref py py-attr docutils literal"><span class="pre">columns</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>A named-based collection of <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> objects
maintained by this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<p>The <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.columns" title="sqlalchemy.sql.expression.GenerativeSelect.columns"><tt class="xref py py-attr docutils literal"><span class="pre">columns</span></tt></a>, or <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.c" title="sqlalchemy.sql.expression.GenerativeSelect.c"><tt class="xref py py-attr docutils literal"><span class="pre">c</span></tt></a> collection, is the gateway
to the construction of SQL expressions using table-bound or
other selectable-bound columns:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">select</span><span class="p">([</span><span class="n">mytable</span><span class="p">])</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="n">mytable</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">somecolumn</span> <span class="o">==</span> <span class="mi">5</span><span class="p">)</span></pre></div>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.compare">
<tt class="descname">compare</tt><big>(</big><em>other</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.compare" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.compare" title="sqlalchemy.sql.expression.ClauseElement.compare"><tt class="xref py py-meth docutils literal"><span class="pre">compare()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Compare this ClauseElement to the given ClauseElement.</p>
<p>Subclasses should override the default behavior, which is a
straight identity comparison.</p>
<p>**kw are arguments consumed by subclass compare() methods and
may be used to modify the criteria for comparison.
(see <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a>)</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.compile">
<tt class="descname">compile</tt><big>(</big><em>bind=None</em>, <em>dialect=None</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.compile" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.compile" title="sqlalchemy.sql.expression.ClauseElement.compile"><tt class="xref py py-meth docutils literal"><span class="pre">compile()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Compile this SQL expression.</p>
<p>The return value is a <a class="reference internal" href="internals.html#sqlalchemy.engine.interfaces.Compiled" title="sqlalchemy.engine.interfaces.Compiled"><tt class="xref py py-class docutils literal"><span class="pre">Compiled</span></tt></a> object.
Calling <tt class="docutils literal"><span class="pre">str()</span></tt> or <tt class="docutils literal"><span class="pre">unicode()</span></tt> on the returned value will yield a
string representation of the result. The
<a class="reference internal" href="internals.html#sqlalchemy.engine.interfaces.Compiled" title="sqlalchemy.engine.interfaces.Compiled"><tt class="xref py py-class docutils literal"><span class="pre">Compiled</span></tt></a> object also can return a
dictionary of bind parameter names and values
using the <tt class="docutils literal"><span class="pre">params</span></tt> accessor.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.GenerativeSelect.compile.params.bind"></span><strong>bind</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.compile.params.bind">¶</a> – An <tt class="docutils literal"><span class="pre">Engine</span></tt> or <tt class="docutils literal"><span class="pre">Connection</span></tt> from which a
<tt class="docutils literal"><span class="pre">Compiled</span></tt> will be acquired. This argument takes precedence over
this <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a>‘s bound engine, if any.</li>
<li><span class="target" id="sqlalchemy.sql.expression.GenerativeSelect.compile.params.column_keys"></span><strong>column_keys</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.compile.params.column_keys">¶</a> – Used for INSERT and UPDATE statements, a list of
column names which should be present in the VALUES clause of the
compiled statement. If <tt class="docutils literal"><span class="pre">None</span></tt>, all columns from the target table
object are rendered.</li>
<li><span class="target" id="sqlalchemy.sql.expression.GenerativeSelect.compile.params.dialect"></span><strong>dialect</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.compile.params.dialect">¶</a> – A <tt class="docutils literal"><span class="pre">Dialect</span></tt> instance from which a <tt class="docutils literal"><span class="pre">Compiled</span></tt>
will be acquired. This argument takes precedence over the <cite>bind</cite>
argument as well as this <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a>‘s bound engine,
if any.</li>
<li><span class="target" id="sqlalchemy.sql.expression.GenerativeSelect.compile.params.inline"></span><strong>inline</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.compile.params.inline">¶</a> – Used for INSERT statements, for a dialect which does
not support inline retrieval of newly generated primary key
columns, will force the expression used to create the new primary
key value to be rendered inline within the INSERT statement’s
VALUES clause. This typically refers to Sequence execution but may
also refer to any server-side default generation function
associated with a primary key <cite>Column</cite>.</li>
<li><span class="target" id="sqlalchemy.sql.expression.GenerativeSelect.compile.params.compile_kwargs"></span><strong>compile_kwargs</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.compile.params.compile_kwargs">¶</a> – <p>optional dictionary of additional parameters
that will be passed through to the compiler within all “visit”
methods. This allows any custom flag to be passed through to
a custom compilation construct, for example. It is also used
for the case of passing the <tt class="docutils literal"><span class="pre">literal_binds</span></tt> flag through:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy.sql</span> <span class="kn">import</span> <span class="n">table</span><span class="p">,</span> <span class="n">column</span><span class="p">,</span> <span class="n">select</span>
<span class="n">t</span> <span class="o">=</span> <span class="n">table</span><span class="p">(</span><span class="s">'t'</span><span class="p">,</span> <span class="n">column</span><span class="p">(</span><span class="s">'x'</span><span class="p">))</span>
<span class="n">s</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">t</span><span class="p">])</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="n">t</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">x</span> <span class="o">==</span> <span class="mi">5</span><span class="p">)</span>
<span class="k">print</span> <span class="n">s</span><span class="o">.</span><span class="n">compile</span><span class="p">(</span><span class="n">compile_kwargs</span><span class="o">=</span><span class="p">{</span><span class="s">"literal_binds"</span><span class="p">:</span> <span class="bp">True</span><span class="p">})</span></pre></div>
</div>
<div class="versionadded">
<p><span>New in version 0.9.0.</span></p>
</div>
</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="../faq.html#faq-sql-expression-string"><em>How do I render SQL expressions as strings, possibly with bound parameters inlined?</em></a></p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.correspond_on_equivalents">
<tt class="descname">correspond_on_equivalents</tt><big>(</big><em>column</em>, <em>equivalents</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.correspond_on_equivalents" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.correspond_on_equivalents" title="sqlalchemy.sql.expression.FromClause.correspond_on_equivalents"><tt class="xref py py-meth docutils literal"><span class="pre">correspond_on_equivalents()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return corresponding_column for the given column, or if None
search for a match in the given dictionary.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.corresponding_column">
<tt class="descname">corresponding_column</tt><big>(</big><em>column</em>, <em>require_embedded=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.corresponding_column" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.corresponding_column" title="sqlalchemy.sql.expression.FromClause.corresponding_column"><tt class="xref py py-meth docutils literal"><span class="pre">corresponding_column()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Given a <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a>, return the exported
<a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> object from this <a class="reference internal" href="#sqlalchemy.sql.expression.Selectable" title="sqlalchemy.sql.expression.Selectable"><tt class="xref py py-class docutils literal"><span class="pre">Selectable</span></tt></a>
which corresponds to that original
<a class="reference internal" href="metadata.html#sqlalchemy.schema.Column" title="sqlalchemy.schema.Column"><tt class="xref py py-class docutils literal"><span class="pre">Column</span></tt></a> via a common ancestor
column.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.GenerativeSelect.corresponding_column.params.column"></span><strong>column</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.corresponding_column.params.column">¶</a> – the target <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> to be matched</li>
<li><span class="target" id="sqlalchemy.sql.expression.GenerativeSelect.corresponding_column.params.require_embedded"></span><strong>require_embedded</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.corresponding_column.params.require_embedded">¶</a> – only return corresponding columns for
the given <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a>, if the given
<a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> is actually present within a sub-element
of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>. Normally the column will match if
it merely shares a common ancestor with one of the exported
columns of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.count">
<tt class="descname">count</tt><big>(</big><em>whereclause=None</em>, <em>**params</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.count" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.count" title="sqlalchemy.sql.expression.FromClause.count"><tt class="xref py py-meth docutils literal"><span class="pre">count()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>return a SELECT COUNT generated against this
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.cte">
<tt class="descname">cte</tt><big>(</big><em>name=None</em>, <em>recursive=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.cte" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase.cte" title="sqlalchemy.sql.expression.SelectBase.cte"><tt class="xref py py-meth docutils literal"><span class="pre">cte()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase" title="sqlalchemy.sql.expression.SelectBase"><tt class="xref py py-class docutils literal"><span class="pre">SelectBase</span></tt></a></div>
<p>Return a new <a class="reference internal" href="#sqlalchemy.sql.expression.CTE" title="sqlalchemy.sql.expression.CTE"><tt class="xref py py-class docutils literal"><span class="pre">CTE</span></tt></a>, or Common Table Expression instance.</p>
<p>Common table expressions are a SQL standard whereby SELECT
statements can draw upon secondary statements specified along
with the primary statement, using a clause called “WITH”.
Special semantics regarding UNION can also be employed to
allow “recursive” queries, where a SELECT statement can draw
upon the set of rows that have previously been selected.</p>
<p>SQLAlchemy detects <a class="reference internal" href="#sqlalchemy.sql.expression.CTE" title="sqlalchemy.sql.expression.CTE"><tt class="xref py py-class docutils literal"><span class="pre">CTE</span></tt></a> objects, which are treated
similarly to <a class="reference internal" href="#sqlalchemy.sql.expression.Alias" title="sqlalchemy.sql.expression.Alias"><tt class="xref py py-class docutils literal"><span class="pre">Alias</span></tt></a> objects, as special elements
to be delivered to the FROM clause of the statement as well
as to a WITH clause at the top of the statement.</p>
<div class="versionadded">
<p><span>New in version 0.7.6.</span></p>
</div>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.GenerativeSelect.cte.params.name"></span><strong>name</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.cte.params.name">¶</a> – name given to the common table expression. Like
<tt class="xref py py-meth docutils literal"><span class="pre">_FromClause.alias()</span></tt>, the name can be left as <tt class="docutils literal"><span class="pre">None</span></tt>
in which case an anonymous symbol will be used at query
compile time.</li>
<li><span class="target" id="sqlalchemy.sql.expression.GenerativeSelect.cte.params.recursive"></span><strong>recursive</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.cte.params.recursive">¶</a> – if <tt class="docutils literal"><span class="pre">True</span></tt>, will render <tt class="docutils literal"><span class="pre">WITH</span> <span class="pre">RECURSIVE</span></tt>.
A recursive common table expression is intended to be used in
conjunction with UNION ALL in order to derive rows
from those already selected.</li>
</ul>
</td>
</tr>
</tbody>
</table>
<p>The following examples illustrate two examples from
Postgresql’s documentation at
<a class="reference external" href="http://www.postgresql.org/docs/8.4/static/queries-with.html">http://www.postgresql.org/docs/8.4/static/queries-with.html</a>.</p>
<p>Example 1, non recursive:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="p">(</span><span class="n">Table</span><span class="p">,</span> <span class="n">Column</span><span class="p">,</span> <span class="n">String</span><span class="p">,</span> <span class="n">Integer</span><span class="p">,</span>
<span class="n">MetaData</span><span class="p">,</span> <span class="n">select</span><span class="p">,</span> <span class="n">func</span><span class="p">)</span>
<span class="n">metadata</span> <span class="o">=</span> <span class="n">MetaData</span><span class="p">()</span>
<span class="n">orders</span> <span class="o">=</span> <span class="n">Table</span><span class="p">(</span><span class="s">'orders'</span><span class="p">,</span> <span class="n">metadata</span><span class="p">,</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'region'</span><span class="p">,</span> <span class="n">String</span><span class="p">),</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'amount'</span><span class="p">,</span> <span class="n">Integer</span><span class="p">),</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'product'</span><span class="p">,</span> <span class="n">String</span><span class="p">),</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'quantity'</span><span class="p">,</span> <span class="n">Integer</span><span class="p">)</span>
<span class="p">)</span>
<span class="n">regional_sales</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span>
<span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">region</span><span class="p">,</span>
<span class="n">func</span><span class="o">.</span><span class="n">sum</span><span class="p">(</span><span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">amount</span><span class="p">)</span><span class="o">.</span><span class="n">label</span><span class="p">(</span><span class="s">'total_sales'</span><span class="p">)</span>
<span class="p">])</span><span class="o">.</span><span class="n">group_by</span><span class="p">(</span><span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">region</span><span class="p">)</span><span class="o">.</span><span class="n">cte</span><span class="p">(</span><span class="s">"regional_sales"</span><span class="p">)</span>
<span class="n">top_regions</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">regional_sales</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">region</span><span class="p">])</span><span class="o">.</span>\
<span class="n">where</span><span class="p">(</span>
<span class="n">regional_sales</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">total_sales</span> <span class="o">></span>
<span class="n">select</span><span class="p">([</span>
<span class="n">func</span><span class="o">.</span><span class="n">sum</span><span class="p">(</span><span class="n">regional_sales</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">total_sales</span><span class="p">)</span><span class="o">/</span><span class="mi">10</span>
<span class="p">])</span>
<span class="p">)</span><span class="o">.</span><span class="n">cte</span><span class="p">(</span><span class="s">"top_regions"</span><span class="p">)</span>
<span class="n">statement</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span>
<span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">region</span><span class="p">,</span>
<span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">product</span><span class="p">,</span>
<span class="n">func</span><span class="o">.</span><span class="n">sum</span><span class="p">(</span><span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">quantity</span><span class="p">)</span><span class="o">.</span><span class="n">label</span><span class="p">(</span><span class="s">"product_units"</span><span class="p">),</span>
<span class="n">func</span><span class="o">.</span><span class="n">sum</span><span class="p">(</span><span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">amount</span><span class="p">)</span><span class="o">.</span><span class="n">label</span><span class="p">(</span><span class="s">"product_sales"</span><span class="p">)</span>
<span class="p">])</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">region</span><span class="o">.</span><span class="n">in_</span><span class="p">(</span>
<span class="n">select</span><span class="p">([</span><span class="n">top_regions</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">region</span><span class="p">])</span>
<span class="p">))</span><span class="o">.</span><span class="n">group_by</span><span class="p">(</span><span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">region</span><span class="p">,</span> <span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">product</span><span class="p">)</span>
<span class="n">result</span> <span class="o">=</span> <span class="n">conn</span><span class="o">.</span><span class="n">execute</span><span class="p">(</span><span class="n">statement</span><span class="p">)</span><span class="o">.</span><span class="n">fetchall</span><span class="p">()</span></pre></div>
</div>
<p>Example 2, WITH RECURSIVE:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="p">(</span><span class="n">Table</span><span class="p">,</span> <span class="n">Column</span><span class="p">,</span> <span class="n">String</span><span class="p">,</span> <span class="n">Integer</span><span class="p">,</span>
<span class="n">MetaData</span><span class="p">,</span> <span class="n">select</span><span class="p">,</span> <span class="n">func</span><span class="p">)</span>
<span class="n">metadata</span> <span class="o">=</span> <span class="n">MetaData</span><span class="p">()</span>
<span class="n">parts</span> <span class="o">=</span> <span class="n">Table</span><span class="p">(</span><span class="s">'parts'</span><span class="p">,</span> <span class="n">metadata</span><span class="p">,</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'part'</span><span class="p">,</span> <span class="n">String</span><span class="p">),</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'sub_part'</span><span class="p">,</span> <span class="n">String</span><span class="p">),</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'quantity'</span><span class="p">,</span> <span class="n">Integer</span><span class="p">),</span>
<span class="p">)</span>
<span class="n">included_parts</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span>
<span class="n">parts</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">sub_part</span><span class="p">,</span>
<span class="n">parts</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">part</span><span class="p">,</span>
<span class="n">parts</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">quantity</span><span class="p">])</span><span class="o">.</span>\
<span class="n">where</span><span class="p">(</span><span class="n">parts</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">part</span><span class="o">==</span><span class="s">'our part'</span><span class="p">)</span><span class="o">.</span>\
<span class="n">cte</span><span class="p">(</span><span class="n">recursive</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span>
<span class="n">incl_alias</span> <span class="o">=</span> <span class="n">included_parts</span><span class="o">.</span><span class="n">alias</span><span class="p">()</span>
<span class="n">parts_alias</span> <span class="o">=</span> <span class="n">parts</span><span class="o">.</span><span class="n">alias</span><span class="p">()</span>
<span class="n">included_parts</span> <span class="o">=</span> <span class="n">included_parts</span><span class="o">.</span><span class="n">union_all</span><span class="p">(</span>
<span class="n">select</span><span class="p">([</span>
<span class="n">parts_alias</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">sub_part</span><span class="p">,</span>
<span class="n">parts_alias</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">part</span><span class="p">,</span>
<span class="n">parts_alias</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">quantity</span>
<span class="p">])</span><span class="o">.</span>
<span class="n">where</span><span class="p">(</span><span class="n">parts_alias</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">part</span><span class="o">==</span><span class="n">incl_alias</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">sub_part</span><span class="p">)</span>
<span class="p">)</span>
<span class="n">statement</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span>
<span class="n">included_parts</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">sub_part</span><span class="p">,</span>
<span class="n">func</span><span class="o">.</span><span class="n">sum</span><span class="p">(</span><span class="n">included_parts</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">quantity</span><span class="p">)</span><span class="o">.</span>
<span class="n">label</span><span class="p">(</span><span class="s">'total_quantity'</span><span class="p">)</span>
<span class="p">])</span><span class="o">.</span>\
<span class="n">group_by</span><span class="p">(</span><span class="n">included_parts</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">sub_part</span><span class="p">)</span>
<span class="n">result</span> <span class="o">=</span> <span class="n">conn</span><span class="o">.</span><span class="n">execute</span><span class="p">(</span><span class="n">statement</span><span class="p">)</span><span class="o">.</span><span class="n">fetchall</span><span class="p">()</span></pre></div>
</div>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="../orm/query.html#sqlalchemy.orm.query.Query.cte" title="sqlalchemy.orm.query.Query.cte"><tt class="xref py py-meth docutils literal"><span class="pre">orm.query.Query.cte()</span></tt></a> - ORM version of
<a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase.cte" title="sqlalchemy.sql.expression.SelectBase.cte"><tt class="xref py py-meth docutils literal"><span class="pre">SelectBase.cte()</span></tt></a>.</p>
</div>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.description">
<tt class="descname">description</tt><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.description" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.description" title="sqlalchemy.sql.expression.FromClause.description"><tt class="xref py py-attr docutils literal"><span class="pre">description</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>a brief description of this FromClause.</p>
<p>Used primarily for error message formatting.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.execute">
<tt class="descname">execute</tt><big>(</big><em>*multiparams</em>, <em>**params</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.execute" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.Executable.execute" title="sqlalchemy.sql.expression.Executable.execute"><tt class="xref py py-meth docutils literal"><span class="pre">execute()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.Executable" title="sqlalchemy.sql.expression.Executable"><tt class="xref py py-class docutils literal"><span class="pre">Executable</span></tt></a></div>
<p>Compile and execute this <a class="reference internal" href="#sqlalchemy.sql.expression.Executable" title="sqlalchemy.sql.expression.Executable"><tt class="xref py py-class docutils literal"><span class="pre">Executable</span></tt></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.execution_options">
<tt class="descname">execution_options</tt><big>(</big><em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.execution_options" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.Executable.execution_options" title="sqlalchemy.sql.expression.Executable.execution_options"><tt class="xref py py-meth docutils literal"><span class="pre">execution_options()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.Executable" title="sqlalchemy.sql.expression.Executable"><tt class="xref py py-class docutils literal"><span class="pre">Executable</span></tt></a></div>
<p>Set non-SQL options for the statement which take effect during
execution.</p>
<p>Execution options can be set on a per-statement or
per <a class="reference internal" href="connections.html#sqlalchemy.engine.Connection" title="sqlalchemy.engine.Connection"><tt class="xref py py-class docutils literal"><span class="pre">Connection</span></tt></a> basis. Additionally, the
<a class="reference internal" href="connections.html#sqlalchemy.engine.Engine" title="sqlalchemy.engine.Engine"><tt class="xref py py-class docutils literal"><span class="pre">Engine</span></tt></a> and ORM <a class="reference internal" href="../orm/query.html#sqlalchemy.orm.query.Query" title="sqlalchemy.orm.query.Query"><tt class="xref py py-class docutils literal"><span class="pre">Query</span></tt></a> objects provide
access to execution options which they in turn configure upon
connections.</p>
<p>The <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.execution_options" title="sqlalchemy.sql.expression.GenerativeSelect.execution_options"><tt class="xref py py-meth docutils literal"><span class="pre">execution_options()</span></tt></a> method is generative. A new
instance of this statement is returned that contains the options:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">statement</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">x</span><span class="p">,</span> <span class="n">table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">y</span><span class="p">])</span>
<span class="n">statement</span> <span class="o">=</span> <span class="n">statement</span><span class="o">.</span><span class="n">execution_options</span><span class="p">(</span><span class="n">autocommit</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span></pre></div>
</div>
<p>Note that only a subset of possible execution options can be applied
to a statement - these include “autocommit” and “stream_results”,
but not “isolation_level” or “compiled_cache”.
See <a class="reference internal" href="connections.html#sqlalchemy.engine.Connection.execution_options" title="sqlalchemy.engine.Connection.execution_options"><tt class="xref py py-meth docutils literal"><span class="pre">Connection.execution_options()</span></tt></a> for a full list of
possible options.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p><a class="reference internal" href="connections.html#sqlalchemy.engine.Connection.execution_options" title="sqlalchemy.engine.Connection.execution_options"><tt class="xref py py-meth docutils literal"><span class="pre">Connection.execution_options()</span></tt></a></p>
<p class="last"><a class="reference internal" href="../orm/query.html#sqlalchemy.orm.query.Query.execution_options" title="sqlalchemy.orm.query.Query.execution_options"><tt class="xref py py-meth docutils literal"><span class="pre">Query.execution_options()</span></tt></a></p>
</div>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.for_update">
<tt class="descname">for_update</tt><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.for_update" title="Permalink to this definition">¶</a></dt>
<dd><p>Provide legacy dialect support for the <tt class="docutils literal"><span class="pre">for_update</span></tt> attribute.</p>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.foreign_keys">
<tt class="descname">foreign_keys</tt><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.foreign_keys" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.foreign_keys" title="sqlalchemy.sql.expression.FromClause.foreign_keys"><tt class="xref py py-attr docutils literal"><span class="pre">foreign_keys</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return the collection of ForeignKey objects which this
FromClause references.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.get_children">
<tt class="descname">get_children</tt><big>(</big><em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.get_children" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.get_children" title="sqlalchemy.sql.expression.ClauseElement.get_children"><tt class="xref py py-meth docutils literal"><span class="pre">get_children()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Return immediate child elements of this <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a>.</p>
<p>This is used for visit traversal.</p>
<p>**kwargs may contain flags that change the collection that is
returned, for example to return a subset of items in order to
cut down on larger traversals, or to return child items from a
different context (such as schema-level collections instead of
clause-level).</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.group_by">
<tt class="descname">group_by</tt><big>(</big><em>*clauses</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.group_by" title="Permalink to this definition">¶</a></dt>
<dd><p>return a new selectable with the given list of GROUP BY
criterion applied.</p>
<p>The criterion will be appended to any pre-existing GROUP BY
criterion.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.is_derived_from">
<tt class="descname">is_derived_from</tt><big>(</big><em>fromclause</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.is_derived_from" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.is_derived_from" title="sqlalchemy.sql.expression.FromClause.is_derived_from"><tt class="xref py py-meth docutils literal"><span class="pre">is_derived_from()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return True if this FromClause is ‘derived’ from the given
FromClause.</p>
<p>An example would be an Alias of a Table is derived from that Table.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.join">
<tt class="descname">join</tt><big>(</big><em>right</em>, <em>onclause=None</em>, <em>isouter=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.join" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">join()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return a <a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> from this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>
to another <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<p>E.g.:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="n">join</span>
<span class="n">j</span> <span class="o">=</span> <span class="n">user_table</span><span class="o">.</span><span class="n">join</span><span class="p">(</span><span class="n">address_table</span><span class="p">,</span>
<span class="n">user_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span> <span class="o">==</span> <span class="n">address_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">user_id</span><span class="p">)</span>
<span class="n">stmt</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">user_table</span><span class="p">])</span><span class="o">.</span><span class="n">select_from</span><span class="p">(</span><span class="n">j</span><span class="p">)</span></pre></div>
</div>
<p>would emit SQL along the lines of:</p>
<div class="highlight-python"><pre>SELECT user.id, user.name FROM user
JOIN address ON user.id = address.user_id</pre>
</div>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.GenerativeSelect.join.params.right"></span><strong>right</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.join.params.right">¶</a> – the right side of the join; this is any
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> object such as a <a class="reference internal" href="metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a> object, and
may also be a selectable-compatible object such as an ORM-mapped
class.</li>
<li><span class="target" id="sqlalchemy.sql.expression.GenerativeSelect.join.params.onclause"></span><strong>onclause</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.join.params.onclause">¶</a> – a SQL expression representing the ON clause of the
join. If left at <tt class="docutils literal"><span class="pre">None</span></tt>, <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a> will attempt to
join the two tables based on a foreign key relationship.</li>
<li><span class="target" id="sqlalchemy.sql.expression.GenerativeSelect.join.params.isouter"></span><strong>isouter</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.join.params.isouter">¶</a> – if True, render a LEFT OUTER JOIN, instead of JOIN.</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p><a class="reference internal" href="#sqlalchemy.sql.expression.join" title="sqlalchemy.sql.expression.join"><tt class="xref py py-func docutils literal"><span class="pre">join()</span></tt></a> - standalone function</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> - the type of object produced</p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.label">
<tt class="descname">label</tt><big>(</big><em>name</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.label" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase.label" title="sqlalchemy.sql.expression.SelectBase.label"><tt class="xref py py-meth docutils literal"><span class="pre">label()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase" title="sqlalchemy.sql.expression.SelectBase"><tt class="xref py py-class docutils literal"><span class="pre">SelectBase</span></tt></a></div>
<p>return a ‘scalar’ representation of this selectable, embedded as a
subquery with a label.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase.as_scalar" title="sqlalchemy.sql.expression.SelectBase.as_scalar"><tt class="xref py py-meth docutils literal"><span class="pre">as_scalar()</span></tt></a>.</p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.limit">
<tt class="descname">limit</tt><big>(</big><em>limit</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.limit" title="Permalink to this definition">¶</a></dt>
<dd><p>return a new selectable with the given LIMIT criterion
applied.</p>
<p>This is a numerical value which usually renders as a <tt class="docutils literal"><span class="pre">LIMIT</span></tt>
expression in the resulting select. Backends that don’t
support <tt class="docutils literal"><span class="pre">LIMIT</span></tt> will attempt to provide similar
functionality.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><span class="target" id="sqlalchemy.sql.expression.GenerativeSelect.limit.params.limit"></span><strong>limit</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.limit.params.limit">¶</a> – an integer LIMIT parameter.</td>
</tr>
</tbody>
</table>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.offset">
<tt class="descname">offset</tt><big>(</big><em>offset</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.offset" title="Permalink to this definition">¶</a></dt>
<dd><p>return a new selectable with the given OFFSET criterion
applied.</p>
<p>This is a numeric value which usually renders as an <tt class="docutils literal"><span class="pre">OFFSET</span></tt>
expression in the resulting select. Backends that don’t
support <tt class="docutils literal"><span class="pre">OFFSET</span></tt> will attempt to provide similar
functionality.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><span class="target" id="sqlalchemy.sql.expression.GenerativeSelect.offset.params.offset"></span><strong>offset</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.offset.params.offset">¶</a> – an integer OFFSET parameter.</td>
</tr>
</tbody>
</table>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.order_by">
<tt class="descname">order_by</tt><big>(</big><em>*clauses</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.order_by" title="Permalink to this definition">¶</a></dt>
<dd><p>return a new selectable with the given list of ORDER BY
criterion applied.</p>
<p>The criterion will be appended to any pre-existing ORDER BY
criterion.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.outerjoin">
<tt class="descname">outerjoin</tt><big>(</big><em>right</em>, <em>onclause=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.outerjoin" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.outerjoin" title="sqlalchemy.sql.expression.FromClause.outerjoin"><tt class="xref py py-meth docutils literal"><span class="pre">outerjoin()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return a <a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> from this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>
to another <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>, with the “isouter” flag set to
True.</p>
<p>E.g.:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="n">outerjoin</span>
<span class="n">j</span> <span class="o">=</span> <span class="n">user_table</span><span class="o">.</span><span class="n">outerjoin</span><span class="p">(</span><span class="n">address_table</span><span class="p">,</span>
<span class="n">user_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span> <span class="o">==</span> <span class="n">address_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">user_id</span><span class="p">)</span></pre></div>
</div>
<p>The above is equivalent to:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">j</span> <span class="o">=</span> <span class="n">user_table</span><span class="o">.</span><span class="n">join</span><span class="p">(</span>
<span class="n">address_table</span><span class="p">,</span>
<span class="n">user_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span> <span class="o">==</span> <span class="n">address_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">user_id</span><span class="p">,</span>
<span class="n">isouter</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span></pre></div>
</div>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.GenerativeSelect.outerjoin.params.right"></span><strong>right</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.outerjoin.params.right">¶</a> – the right side of the join; this is any
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> object such as a <a class="reference internal" href="metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a> object, and
may also be a selectable-compatible object such as an ORM-mapped
class.</li>
<li><span class="target" id="sqlalchemy.sql.expression.GenerativeSelect.outerjoin.params.onclause"></span><strong>onclause</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.outerjoin.params.onclause">¶</a> – a SQL expression representing the ON clause of the
join. If left at <tt class="docutils literal"><span class="pre">None</span></tt>, <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a> will attempt to
join the two tables based on a foreign key relationship.</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p><a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a></p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a></p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.params">
<tt class="descname">params</tt><big>(</big><em>*optionaldict</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.params" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.params" title="sqlalchemy.sql.expression.ClauseElement.params"><tt class="xref py py-meth docutils literal"><span class="pre">params()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Return a copy with <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.bindparam" title="sqlalchemy.sql.expression.bindparam"><tt class="xref py py-func docutils literal"><span class="pre">bindparam()</span></tt></a> elements replaced.</p>
<p>Returns a copy of this ClauseElement with <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.bindparam" title="sqlalchemy.sql.expression.bindparam"><tt class="xref py py-func docutils literal"><span class="pre">bindparam()</span></tt></a>
elements replaced with values taken from the given dictionary:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="n">clause</span> <span class="o">=</span> <span class="n">column</span><span class="p">(</span><span class="s">'x'</span><span class="p">)</span> <span class="o">+</span> <span class="n">bindparam</span><span class="p">(</span><span class="s">'foo'</span><span class="p">)</span>
<span class="gp">>>> </span><span class="k">print</span> <span class="n">clause</span><span class="o">.</span><span class="n">compile</span><span class="p">()</span><span class="o">.</span><span class="n">params</span>
<span class="go">{'foo':None}</span>
<span class="gp">>>> </span><span class="k">print</span> <span class="n">clause</span><span class="o">.</span><span class="n">params</span><span class="p">({</span><span class="s">'foo'</span><span class="p">:</span><span class="mi">7</span><span class="p">})</span><span class="o">.</span><span class="n">compile</span><span class="p">()</span><span class="o">.</span><span class="n">params</span>
<span class="go">{'foo':7}</span></pre></div>
</div>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.primary_key">
<tt class="descname">primary_key</tt><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.primary_key" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.primary_key" title="sqlalchemy.sql.expression.FromClause.primary_key"><tt class="xref py py-attr docutils literal"><span class="pre">primary_key</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return the collection of Column objects which comprise the
primary key of this FromClause.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.replace_selectable">
<tt class="descname">replace_selectable</tt><big>(</big><em>old</em>, <em>alias</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.replace_selectable" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.replace_selectable" title="sqlalchemy.sql.expression.FromClause.replace_selectable"><tt class="xref py py-meth docutils literal"><span class="pre">replace_selectable()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>replace all occurrences of FromClause ‘old’ with the given Alias
object, returning a copy of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.scalar">
<tt class="descname">scalar</tt><big>(</big><em>*multiparams</em>, <em>**params</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.scalar" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.Executable.scalar" title="sqlalchemy.sql.expression.Executable.scalar"><tt class="xref py py-meth docutils literal"><span class="pre">scalar()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.Executable" title="sqlalchemy.sql.expression.Executable"><tt class="xref py py-class docutils literal"><span class="pre">Executable</span></tt></a></div>
<p>Compile and execute this <a class="reference internal" href="#sqlalchemy.sql.expression.Executable" title="sqlalchemy.sql.expression.Executable"><tt class="xref py py-class docutils literal"><span class="pre">Executable</span></tt></a>, returning the
result’s scalar representation.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.select">
<tt class="descname">select</tt><big>(</big><em>whereclause=None</em>, <em>**params</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.select" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.select" title="sqlalchemy.sql.expression.FromClause.select"><tt class="xref py py-meth docutils literal"><span class="pre">select()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>return a SELECT of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a> - general purpose
method which allows for arbitrary column lists.</p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.self_group">
<tt class="descname">self_group</tt><big>(</big><em>against=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.self_group" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.self_group" title="sqlalchemy.sql.expression.ClauseElement.self_group"><tt class="xref py py-meth docutils literal"><span class="pre">self_group()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Apply a ‘grouping’ to this <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a>.</p>
<p>This method is overridden by subclasses to return a
“grouping” construct, i.e. parenthesis. In particular
it’s used by “binary” expressions to provide a grouping
around themselves when placed into a larger expression,
as well as by <a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a> constructs when placed into
the FROM clause of another <a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a>. (Note that
subqueries should be normally created using the
<a class="reference internal" href="#sqlalchemy.sql.expression.Select.alias" title="sqlalchemy.sql.expression.Select.alias"><tt class="xref py py-meth docutils literal"><span class="pre">Select.alias()</span></tt></a> method, as many platforms require
nested SELECT statements to be named).</p>
<p>As expressions are composed together, the application of
<a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.self_group" title="sqlalchemy.sql.expression.GenerativeSelect.self_group"><tt class="xref py py-meth docutils literal"><span class="pre">self_group()</span></tt></a> is automatic - end-user code should never
need to use this method directly. Note that SQLAlchemy’s
clause constructs take operator precedence into account -
so parenthesis might not be needed, for example, in
an expression like <tt class="docutils literal"><span class="pre">x</span> <span class="pre">OR</span> <span class="pre">(y</span> <span class="pre">AND</span> <span class="pre">z)</span></tt> - AND takes precedence
over OR.</p>
<p>The base <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.self_group" title="sqlalchemy.sql.expression.GenerativeSelect.self_group"><tt class="xref py py-meth docutils literal"><span class="pre">self_group()</span></tt></a> method of <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a>
just returns self.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.unique_params">
<tt class="descname">unique_params</tt><big>(</big><em>*optionaldict</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.unique_params" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.unique_params" title="sqlalchemy.sql.expression.ClauseElement.unique_params"><tt class="xref py py-meth docutils literal"><span class="pre">unique_params()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Return a copy with <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.bindparam" title="sqlalchemy.sql.expression.bindparam"><tt class="xref py py-func docutils literal"><span class="pre">bindparam()</span></tt></a> elements replaced.</p>
<p>Same functionality as <tt class="docutils literal"><span class="pre">params()</span></tt>, except adds <cite>unique=True</cite>
to affected bind parameters so that multiple statements can be
used.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.GenerativeSelect.with_for_update">
<tt class="descname">with_for_update</tt><big>(</big><em>nowait=False</em>, <em>read=False</em>, <em>of=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.GenerativeSelect.with_for_update" title="Permalink to this definition">¶</a></dt>
<dd><p>Specify a <tt class="docutils literal"><span class="pre">FOR</span> <span class="pre">UPDATE</span></tt> clause for this <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect" title="sqlalchemy.sql.expression.GenerativeSelect"><tt class="xref py py-class docutils literal"><span class="pre">GenerativeSelect</span></tt></a>.</p>
<p>E.g.:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">stmt</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">table</span><span class="p">])</span><span class="o">.</span><span class="n">with_for_update</span><span class="p">(</span><span class="n">nowait</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span></pre></div>
</div>
<p>On a database like Postgresql or Oracle, the above would render a
statement like:</p>
<div class="highlight-python"><pre>SELECT table.a, table.b FROM table FOR UPDATE NOWAIT</pre>
</div>
<p>on other backends, the <tt class="docutils literal"><span class="pre">nowait</span></tt> option is ignored and instead
would produce:</p>
<div class="highlight-python"><pre>SELECT table.a, table.b FROM table FOR UPDATE</pre>
</div>
<p>When called with no arguments, the statement will render with
the suffix <tt class="docutils literal"><span class="pre">FOR</span> <span class="pre">UPDATE</span></tt>. Additional arguments can then be
provided which allow for common database-specific
variants.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.GenerativeSelect.with_for_update.params.nowait"></span><strong>nowait</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.with_for_update.params.nowait">¶</a> – boolean; will render <tt class="docutils literal"><span class="pre">FOR</span> <span class="pre">UPDATE</span> <span class="pre">NOWAIT</span></tt> on Oracle
and Postgresql dialects.</li>
<li><span class="target" id="sqlalchemy.sql.expression.GenerativeSelect.with_for_update.params.read"></span><strong>read</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.with_for_update.params.read">¶</a> – boolean; will render <tt class="docutils literal"><span class="pre">LOCK</span> <span class="pre">IN</span> <span class="pre">SHARE</span> <span class="pre">MODE</span></tt> on MySQL,
<tt class="docutils literal"><span class="pre">FOR</span> <span class="pre">SHARE</span></tt> on Postgresql. On Postgresql, when combined with
<tt class="docutils literal"><span class="pre">nowait</span></tt>, will render <tt class="docutils literal"><span class="pre">FOR</span> <span class="pre">SHARE</span> <span class="pre">NOWAIT</span></tt>.</li>
<li><span class="target" id="sqlalchemy.sql.expression.GenerativeSelect.with_for_update.params.of"></span><strong>of</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.with_for_update.params.of">¶</a> – SQL expression or list of SQL expression elements
(typically <a class="reference internal" href="metadata.html#sqlalchemy.schema.Column" title="sqlalchemy.schema.Column"><tt class="xref py py-class docutils literal"><span class="pre">Column</span></tt></a> objects or a compatible expression) which
will render into a <tt class="docutils literal"><span class="pre">FOR</span> <span class="pre">UPDATE</span> <span class="pre">OF</span></tt> clause; supported by PostgreSQL
and Oracle. May render as a table or as a column depending on
backend.</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="versionadded">
<p><span>New in version 0.9.0.</span></p>
</div>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.sql.expression.HasPrefixes">
<em class="property">class </em><tt class="descclassname">sqlalchemy.sql.expression.</tt><tt class="descname">HasPrefixes</tt><a class="headerlink" href="#sqlalchemy.sql.expression.HasPrefixes" title="Permalink to this definition">¶</a></dt>
<dd><dl class="method">
<dt id="sqlalchemy.sql.expression.HasPrefixes.prefix_with">
<tt class="descname">prefix_with</tt><big>(</big><em>*expr</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.HasPrefixes.prefix_with" title="Permalink to this definition">¶</a></dt>
<dd><p>Add one or more expressions following the statement keyword, i.e.
SELECT, INSERT, UPDATE, or DELETE. Generative.</p>
<p>This is used to support backend-specific prefix keywords such as those
provided by MySQL.</p>
<p>E.g.:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">stmt</span> <span class="o">=</span> <span class="n">table</span><span class="o">.</span><span class="n">insert</span><span class="p">()</span><span class="o">.</span><span class="n">prefix_with</span><span class="p">(</span><span class="s">"LOW_PRIORITY"</span><span class="p">,</span> <span class="n">dialect</span><span class="o">=</span><span class="s">"mysql"</span><span class="p">)</span></pre></div>
</div>
<p>Multiple prefixes can be specified by multiple calls
to <a class="reference internal" href="#sqlalchemy.sql.expression.HasPrefixes.prefix_with" title="sqlalchemy.sql.expression.HasPrefixes.prefix_with"><tt class="xref py py-meth docutils literal"><span class="pre">prefix_with()</span></tt></a>.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.HasPrefixes.prefix_with.params.*expr"></span><strong>*expr</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.HasPrefixes.prefix_with.params.*expr">¶</a> – textual or <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a> construct which
will be rendered following the INSERT, UPDATE, or DELETE
keyword.</li>
<li><span class="target" id="sqlalchemy.sql.expression.HasPrefixes.prefix_with.params.**kw"></span><strong>**kw</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.HasPrefixes.prefix_with.params.**kw">¶</a> – A single keyword ‘dialect’ is accepted. This is an
optional string dialect name which will
limit rendering of this prefix to only that dialect.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.sql.expression.Join">
<em class="property">class </em><tt class="descclassname">sqlalchemy.sql.expression.</tt><tt class="descname">Join</tt><big>(</big><em>left</em>, <em>right</em>, <em>onclause=None</em>, <em>isouter=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Join" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.sql.expression.FromClause</span></tt></a></p>
<p>represent a <tt class="docutils literal"><span class="pre">JOIN</span></tt> construct between two <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>
elements.</p>
<p>The public constructor function for <a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> is the module-level
<a class="reference internal" href="#sqlalchemy.sql.expression.join" title="sqlalchemy.sql.expression.join"><tt class="xref py py-func docutils literal"><span class="pre">join()</span></tt></a> function, as well as the <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a> method
of any <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> (e.g. such as <a class="reference internal" href="metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a>).</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p><a class="reference internal" href="#sqlalchemy.sql.expression.join" title="sqlalchemy.sql.expression.join"><tt class="xref py py-func docutils literal"><span class="pre">join()</span></tt></a></p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a></p>
</div>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Join.__init__">
<tt class="descname">__init__</tt><big>(</big><em>left</em>, <em>right</em>, <em>onclause=None</em>, <em>isouter=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Join.__init__" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct a new <a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a>.</p>
<p>The usual entrypoint here is the <a class="reference internal" href="#sqlalchemy.sql.expression.join" title="sqlalchemy.sql.expression.join"><tt class="xref py py-func docutils literal"><span class="pre">join()</span></tt></a>
function or the <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a> method of any
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> object.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Join.alias">
<tt class="descname">alias</tt><big>(</big><em>name=None</em>, <em>flat=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Join.alias" title="Permalink to this definition">¶</a></dt>
<dd><p>return an alias of this <a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a>.</p>
<p>The default behavior here is to first produce a SELECT
construct from this <a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a>, then to produce a
<a class="reference internal" href="#sqlalchemy.sql.expression.Alias" title="sqlalchemy.sql.expression.Alias"><tt class="xref py py-class docutils literal"><span class="pre">Alias</span></tt></a> from that. So given a join of the form:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">j</span> <span class="o">=</span> <span class="n">table_a</span><span class="o">.</span><span class="n">join</span><span class="p">(</span><span class="n">table_b</span><span class="p">,</span> <span class="n">table_a</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span> <span class="o">==</span> <span class="n">table_b</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">a_id</span><span class="p">)</span></pre></div>
</div>
<p>The JOIN by itself would look like:</p>
<div class="highlight-python"><pre>table_a JOIN table_b ON table_a.id = table_b.a_id</pre>
</div>
<p>Whereas the alias of the above, <tt class="docutils literal"><span class="pre">j.alias()</span></tt>, would in a
SELECT context look like:</p>
<div class="highlight-python"><pre>(SELECT table_a.id AS table_a_id, table_b.id AS table_b_id,
table_b.a_id AS table_b_a_id
FROM table_a
JOIN table_b ON table_a.id = table_b.a_id) AS anon_1</pre>
</div>
<p>The equivalent long-hand form, given a <a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> object
<tt class="docutils literal"><span class="pre">j</span></tt>, is:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="n">select</span><span class="p">,</span> <span class="n">alias</span>
<span class="n">j</span> <span class="o">=</span> <span class="n">alias</span><span class="p">(</span>
<span class="n">select</span><span class="p">([</span><span class="n">j</span><span class="o">.</span><span class="n">left</span><span class="p">,</span> <span class="n">j</span><span class="o">.</span><span class="n">right</span><span class="p">])</span><span class="o">.</span>\
<span class="n">select_from</span><span class="p">(</span><span class="n">j</span><span class="p">)</span><span class="o">.</span>\
<span class="n">with_labels</span><span class="p">(</span><span class="bp">True</span><span class="p">)</span><span class="o">.</span>\
<span class="n">correlate</span><span class="p">(</span><span class="bp">False</span><span class="p">),</span>
<span class="n">name</span><span class="o">=</span><span class="n">name</span>
<span class="p">)</span></pre></div>
</div>
<p>The selectable produced by <a class="reference internal" href="#sqlalchemy.sql.expression.Join.alias" title="sqlalchemy.sql.expression.Join.alias"><tt class="xref py py-meth docutils literal"><span class="pre">Join.alias()</span></tt></a> features the same
columns as that of the two individual selectables presented under
a single name - the individual columns are “auto-labeled”, meaning
the <tt class="docutils literal"><span class="pre">.c.</span></tt> collection of the resulting <a class="reference internal" href="#sqlalchemy.sql.expression.Alias" title="sqlalchemy.sql.expression.Alias"><tt class="xref py py-class docutils literal"><span class="pre">Alias</span></tt></a> represents
the names of the individual columns using a
<tt class="docutils literal"><span class="pre"><tablename>_<columname></span></tt> scheme:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">j</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">table_a_id</span>
<span class="n">j</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">table_b_a_id</span></pre></div>
</div>
<p><a class="reference internal" href="#sqlalchemy.sql.expression.Join.alias" title="sqlalchemy.sql.expression.Join.alias"><tt class="xref py py-meth docutils literal"><span class="pre">Join.alias()</span></tt></a> also features an alternate
option for aliasing joins which produces no enclosing SELECT and
does not normally apply labels to the column names. The
<tt class="docutils literal"><span class="pre">flat=True</span></tt> option will call <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.alias" title="sqlalchemy.sql.expression.FromClause.alias"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.alias()</span></tt></a>
against the left and right sides individually.
Using this option, no new <tt class="docutils literal"><span class="pre">SELECT</span></tt> is produced;
we instead, from a construct as below:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">j</span> <span class="o">=</span> <span class="n">table_a</span><span class="o">.</span><span class="n">join</span><span class="p">(</span><span class="n">table_b</span><span class="p">,</span> <span class="n">table_a</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span> <span class="o">==</span> <span class="n">table_b</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">a_id</span><span class="p">)</span>
<span class="n">j</span> <span class="o">=</span> <span class="n">j</span><span class="o">.</span><span class="n">alias</span><span class="p">(</span><span class="n">flat</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span></pre></div>
</div>
<p>we get a result like this:</p>
<div class="highlight-python"><pre>table_a AS table_a_1 JOIN table_b AS table_b_1 ON
table_a_1.id = table_b_1.a_id</pre>
</div>
<p>The <tt class="docutils literal"><span class="pre">flat=True</span></tt> argument is also propagated to the contained
selectables, so that a composite join such as:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">j</span> <span class="o">=</span> <span class="n">table_a</span><span class="o">.</span><span class="n">join</span><span class="p">(</span>
<span class="n">table_b</span><span class="o">.</span><span class="n">join</span><span class="p">(</span><span class="n">table_c</span><span class="p">,</span>
<span class="n">table_b</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span> <span class="o">==</span> <span class="n">table_c</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">b_id</span><span class="p">),</span>
<span class="n">table_b</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">a_id</span> <span class="o">==</span> <span class="n">table_a</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span>
<span class="p">)</span><span class="o">.</span><span class="n">alias</span><span class="p">(</span><span class="n">flat</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span></pre></div>
</div>
<p>Will produce an expression like:</p>
<div class="highlight-python"><pre>table_a AS table_a_1 JOIN (
table_b AS table_b_1 JOIN table_c AS table_c_1
ON table_b_1.id = table_c_1.b_id
) ON table_a_1.id = table_b_1.a_id</pre>
</div>
<p>The standalone <a class="reference internal" href="#sqlalchemy.sql.expression.alias" title="sqlalchemy.sql.expression.alias"><tt class="xref py py-func docutils literal"><span class="pre">alias()</span></tt></a> function as well as the
base <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.alias" title="sqlalchemy.sql.expression.FromClause.alias"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.alias()</span></tt></a> method also support the <tt class="docutils literal"><span class="pre">flat=True</span></tt>
argument as a no-op, so that the argument can be passed to the
<tt class="docutils literal"><span class="pre">alias()</span></tt> method of any selectable.</p>
<div class="versionadded">
<p><span>New in version 0.9.0: </span>Added the <tt class="docutils literal"><span class="pre">flat=True</span></tt> option to create
“aliases” of joins without enclosing inside of a SELECT
subquery.</p>
</div>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.Join.alias.params.name"></span><strong>name</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Join.alias.params.name">¶</a> – name given to the alias.</li>
<li><span class="target" id="sqlalchemy.sql.expression.Join.alias.params.flat"></span><strong>flat</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Join.alias.params.flat">¶</a> – <p>if True, produce an alias of the left and right
sides of this <a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> and return the join of those
two selectables. This produces join expression that does not
include an enclosing SELECT.</p>
<div class="versionadded">
<p><span>New in version 0.9.0.</span></p>
</div>
</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.alias" title="sqlalchemy.sql.expression.alias"><tt class="xref py py-func docutils literal"><span class="pre">alias()</span></tt></a></p>
</div>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.Join.c">
<tt class="descname">c</tt><a class="headerlink" href="#sqlalchemy.sql.expression.Join.c" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.c" title="sqlalchemy.sql.expression.FromClause.c"><tt class="xref py py-attr docutils literal"><span class="pre">c</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>An alias for the <a class="reference internal" href="#sqlalchemy.sql.expression.Join.columns" title="sqlalchemy.sql.expression.Join.columns"><tt class="xref py py-attr docutils literal"><span class="pre">columns</span></tt></a> attribute.</p>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.Join.columns">
<tt class="descname">columns</tt><a class="headerlink" href="#sqlalchemy.sql.expression.Join.columns" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.columns" title="sqlalchemy.sql.expression.FromClause.columns"><tt class="xref py py-attr docutils literal"><span class="pre">columns</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>A named-based collection of <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> objects
maintained by this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<p>The <a class="reference internal" href="#sqlalchemy.sql.expression.Join.columns" title="sqlalchemy.sql.expression.Join.columns"><tt class="xref py py-attr docutils literal"><span class="pre">columns</span></tt></a>, or <a class="reference internal" href="#sqlalchemy.sql.expression.Join.c" title="sqlalchemy.sql.expression.Join.c"><tt class="xref py py-attr docutils literal"><span class="pre">c</span></tt></a> collection, is the gateway
to the construction of SQL expressions using table-bound or
other selectable-bound columns:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">select</span><span class="p">([</span><span class="n">mytable</span><span class="p">])</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="n">mytable</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">somecolumn</span> <span class="o">==</span> <span class="mi">5</span><span class="p">)</span></pre></div>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Join.compare">
<tt class="descname">compare</tt><big>(</big><em>other</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Join.compare" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.compare" title="sqlalchemy.sql.expression.ClauseElement.compare"><tt class="xref py py-meth docutils literal"><span class="pre">compare()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Compare this ClauseElement to the given ClauseElement.</p>
<p>Subclasses should override the default behavior, which is a
straight identity comparison.</p>
<p>**kw are arguments consumed by subclass compare() methods and
may be used to modify the criteria for comparison.
(see <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a>)</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Join.compile">
<tt class="descname">compile</tt><big>(</big><em>bind=None</em>, <em>dialect=None</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Join.compile" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.compile" title="sqlalchemy.sql.expression.ClauseElement.compile"><tt class="xref py py-meth docutils literal"><span class="pre">compile()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Compile this SQL expression.</p>
<p>The return value is a <a class="reference internal" href="internals.html#sqlalchemy.engine.interfaces.Compiled" title="sqlalchemy.engine.interfaces.Compiled"><tt class="xref py py-class docutils literal"><span class="pre">Compiled</span></tt></a> object.
Calling <tt class="docutils literal"><span class="pre">str()</span></tt> or <tt class="docutils literal"><span class="pre">unicode()</span></tt> on the returned value will yield a
string representation of the result. The
<a class="reference internal" href="internals.html#sqlalchemy.engine.interfaces.Compiled" title="sqlalchemy.engine.interfaces.Compiled"><tt class="xref py py-class docutils literal"><span class="pre">Compiled</span></tt></a> object also can return a
dictionary of bind parameter names and values
using the <tt class="docutils literal"><span class="pre">params</span></tt> accessor.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.Join.compile.params.bind"></span><strong>bind</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Join.compile.params.bind">¶</a> – An <tt class="docutils literal"><span class="pre">Engine</span></tt> or <tt class="docutils literal"><span class="pre">Connection</span></tt> from which a
<tt class="docutils literal"><span class="pre">Compiled</span></tt> will be acquired. This argument takes precedence over
this <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a>‘s bound engine, if any.</li>
<li><span class="target" id="sqlalchemy.sql.expression.Join.compile.params.column_keys"></span><strong>column_keys</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Join.compile.params.column_keys">¶</a> – Used for INSERT and UPDATE statements, a list of
column names which should be present in the VALUES clause of the
compiled statement. If <tt class="docutils literal"><span class="pre">None</span></tt>, all columns from the target table
object are rendered.</li>
<li><span class="target" id="sqlalchemy.sql.expression.Join.compile.params.dialect"></span><strong>dialect</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Join.compile.params.dialect">¶</a> – A <tt class="docutils literal"><span class="pre">Dialect</span></tt> instance from which a <tt class="docutils literal"><span class="pre">Compiled</span></tt>
will be acquired. This argument takes precedence over the <cite>bind</cite>
argument as well as this <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a>‘s bound engine,
if any.</li>
<li><span class="target" id="sqlalchemy.sql.expression.Join.compile.params.inline"></span><strong>inline</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Join.compile.params.inline">¶</a> – Used for INSERT statements, for a dialect which does
not support inline retrieval of newly generated primary key
columns, will force the expression used to create the new primary
key value to be rendered inline within the INSERT statement’s
VALUES clause. This typically refers to Sequence execution but may
also refer to any server-side default generation function
associated with a primary key <cite>Column</cite>.</li>
<li><span class="target" id="sqlalchemy.sql.expression.Join.compile.params.compile_kwargs"></span><strong>compile_kwargs</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Join.compile.params.compile_kwargs">¶</a> – <p>optional dictionary of additional parameters
that will be passed through to the compiler within all “visit”
methods. This allows any custom flag to be passed through to
a custom compilation construct, for example. It is also used
for the case of passing the <tt class="docutils literal"><span class="pre">literal_binds</span></tt> flag through:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy.sql</span> <span class="kn">import</span> <span class="n">table</span><span class="p">,</span> <span class="n">column</span><span class="p">,</span> <span class="n">select</span>
<span class="n">t</span> <span class="o">=</span> <span class="n">table</span><span class="p">(</span><span class="s">'t'</span><span class="p">,</span> <span class="n">column</span><span class="p">(</span><span class="s">'x'</span><span class="p">))</span>
<span class="n">s</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">t</span><span class="p">])</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="n">t</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">x</span> <span class="o">==</span> <span class="mi">5</span><span class="p">)</span>
<span class="k">print</span> <span class="n">s</span><span class="o">.</span><span class="n">compile</span><span class="p">(</span><span class="n">compile_kwargs</span><span class="o">=</span><span class="p">{</span><span class="s">"literal_binds"</span><span class="p">:</span> <span class="bp">True</span><span class="p">})</span></pre></div>
</div>
<div class="versionadded">
<p><span>New in version 0.9.0.</span></p>
</div>
</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="../faq.html#faq-sql-expression-string"><em>How do I render SQL expressions as strings, possibly with bound parameters inlined?</em></a></p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Join.correspond_on_equivalents">
<tt class="descname">correspond_on_equivalents</tt><big>(</big><em>column</em>, <em>equivalents</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Join.correspond_on_equivalents" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.correspond_on_equivalents" title="sqlalchemy.sql.expression.FromClause.correspond_on_equivalents"><tt class="xref py py-meth docutils literal"><span class="pre">correspond_on_equivalents()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return corresponding_column for the given column, or if None
search for a match in the given dictionary.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Join.corresponding_column">
<tt class="descname">corresponding_column</tt><big>(</big><em>column</em>, <em>require_embedded=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Join.corresponding_column" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.corresponding_column" title="sqlalchemy.sql.expression.FromClause.corresponding_column"><tt class="xref py py-meth docutils literal"><span class="pre">corresponding_column()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Given a <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a>, return the exported
<a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> object from this <a class="reference internal" href="#sqlalchemy.sql.expression.Selectable" title="sqlalchemy.sql.expression.Selectable"><tt class="xref py py-class docutils literal"><span class="pre">Selectable</span></tt></a>
which corresponds to that original
<a class="reference internal" href="metadata.html#sqlalchemy.schema.Column" title="sqlalchemy.schema.Column"><tt class="xref py py-class docutils literal"><span class="pre">Column</span></tt></a> via a common ancestor
column.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.Join.corresponding_column.params.column"></span><strong>column</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Join.corresponding_column.params.column">¶</a> – the target <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> to be matched</li>
<li><span class="target" id="sqlalchemy.sql.expression.Join.corresponding_column.params.require_embedded"></span><strong>require_embedded</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Join.corresponding_column.params.require_embedded">¶</a> – only return corresponding columns for
the given <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a>, if the given
<a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> is actually present within a sub-element
of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>. Normally the column will match if
it merely shares a common ancestor with one of the exported
columns of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Join.count">
<tt class="descname">count</tt><big>(</big><em>whereclause=None</em>, <em>**params</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Join.count" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.count" title="sqlalchemy.sql.expression.FromClause.count"><tt class="xref py py-meth docutils literal"><span class="pre">count()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>return a SELECT COUNT generated against this
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.Join.foreign_keys">
<tt class="descname">foreign_keys</tt><a class="headerlink" href="#sqlalchemy.sql.expression.Join.foreign_keys" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.foreign_keys" title="sqlalchemy.sql.expression.FromClause.foreign_keys"><tt class="xref py py-attr docutils literal"><span class="pre">foreign_keys</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return the collection of ForeignKey objects which this
FromClause references.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Join.join">
<tt class="descname">join</tt><big>(</big><em>right</em>, <em>onclause=None</em>, <em>isouter=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Join.join" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">join()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return a <a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> from this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>
to another <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<p>E.g.:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="n">join</span>
<span class="n">j</span> <span class="o">=</span> <span class="n">user_table</span><span class="o">.</span><span class="n">join</span><span class="p">(</span><span class="n">address_table</span><span class="p">,</span>
<span class="n">user_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span> <span class="o">==</span> <span class="n">address_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">user_id</span><span class="p">)</span>
<span class="n">stmt</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">user_table</span><span class="p">])</span><span class="o">.</span><span class="n">select_from</span><span class="p">(</span><span class="n">j</span><span class="p">)</span></pre></div>
</div>
<p>would emit SQL along the lines of:</p>
<div class="highlight-python"><pre>SELECT user.id, user.name FROM user
JOIN address ON user.id = address.user_id</pre>
</div>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.Join.join.params.right"></span><strong>right</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Join.join.params.right">¶</a> – the right side of the join; this is any
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> object such as a <a class="reference internal" href="metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a> object, and
may also be a selectable-compatible object such as an ORM-mapped
class.</li>
<li><span class="target" id="sqlalchemy.sql.expression.Join.join.params.onclause"></span><strong>onclause</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Join.join.params.onclause">¶</a> – a SQL expression representing the ON clause of the
join. If left at <tt class="docutils literal"><span class="pre">None</span></tt>, <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a> will attempt to
join the two tables based on a foreign key relationship.</li>
<li><span class="target" id="sqlalchemy.sql.expression.Join.join.params.isouter"></span><strong>isouter</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Join.join.params.isouter">¶</a> – if True, render a LEFT OUTER JOIN, instead of JOIN.</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p><a class="reference internal" href="#sqlalchemy.sql.expression.join" title="sqlalchemy.sql.expression.join"><tt class="xref py py-func docutils literal"><span class="pre">join()</span></tt></a> - standalone function</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> - the type of object produced</p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Join.outerjoin">
<tt class="descname">outerjoin</tt><big>(</big><em>right</em>, <em>onclause=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Join.outerjoin" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.outerjoin" title="sqlalchemy.sql.expression.FromClause.outerjoin"><tt class="xref py py-meth docutils literal"><span class="pre">outerjoin()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return a <a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> from this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>
to another <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>, with the “isouter” flag set to
True.</p>
<p>E.g.:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="n">outerjoin</span>
<span class="n">j</span> <span class="o">=</span> <span class="n">user_table</span><span class="o">.</span><span class="n">outerjoin</span><span class="p">(</span><span class="n">address_table</span><span class="p">,</span>
<span class="n">user_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span> <span class="o">==</span> <span class="n">address_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">user_id</span><span class="p">)</span></pre></div>
</div>
<p>The above is equivalent to:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">j</span> <span class="o">=</span> <span class="n">user_table</span><span class="o">.</span><span class="n">join</span><span class="p">(</span>
<span class="n">address_table</span><span class="p">,</span>
<span class="n">user_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span> <span class="o">==</span> <span class="n">address_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">user_id</span><span class="p">,</span>
<span class="n">isouter</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span></pre></div>
</div>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.Join.outerjoin.params.right"></span><strong>right</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Join.outerjoin.params.right">¶</a> – the right side of the join; this is any
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> object such as a <a class="reference internal" href="metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a> object, and
may also be a selectable-compatible object such as an ORM-mapped
class.</li>
<li><span class="target" id="sqlalchemy.sql.expression.Join.outerjoin.params.onclause"></span><strong>onclause</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Join.outerjoin.params.onclause">¶</a> – a SQL expression representing the ON clause of the
join. If left at <tt class="docutils literal"><span class="pre">None</span></tt>, <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a> will attempt to
join the two tables based on a foreign key relationship.</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p><a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a></p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a></p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Join.params">
<tt class="descname">params</tt><big>(</big><em>*optionaldict</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Join.params" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.params" title="sqlalchemy.sql.expression.ClauseElement.params"><tt class="xref py py-meth docutils literal"><span class="pre">params()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Return a copy with <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.bindparam" title="sqlalchemy.sql.expression.bindparam"><tt class="xref py py-func docutils literal"><span class="pre">bindparam()</span></tt></a> elements replaced.</p>
<p>Returns a copy of this ClauseElement with <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.bindparam" title="sqlalchemy.sql.expression.bindparam"><tt class="xref py py-func docutils literal"><span class="pre">bindparam()</span></tt></a>
elements replaced with values taken from the given dictionary:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="n">clause</span> <span class="o">=</span> <span class="n">column</span><span class="p">(</span><span class="s">'x'</span><span class="p">)</span> <span class="o">+</span> <span class="n">bindparam</span><span class="p">(</span><span class="s">'foo'</span><span class="p">)</span>
<span class="gp">>>> </span><span class="k">print</span> <span class="n">clause</span><span class="o">.</span><span class="n">compile</span><span class="p">()</span><span class="o">.</span><span class="n">params</span>
<span class="go">{'foo':None}</span>
<span class="gp">>>> </span><span class="k">print</span> <span class="n">clause</span><span class="o">.</span><span class="n">params</span><span class="p">({</span><span class="s">'foo'</span><span class="p">:</span><span class="mi">7</span><span class="p">})</span><span class="o">.</span><span class="n">compile</span><span class="p">()</span><span class="o">.</span><span class="n">params</span>
<span class="go">{'foo':7}</span></pre></div>
</div>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.Join.primary_key">
<tt class="descname">primary_key</tt><a class="headerlink" href="#sqlalchemy.sql.expression.Join.primary_key" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.primary_key" title="sqlalchemy.sql.expression.FromClause.primary_key"><tt class="xref py py-attr docutils literal"><span class="pre">primary_key</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return the collection of Column objects which comprise the
primary key of this FromClause.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Join.replace_selectable">
<tt class="descname">replace_selectable</tt><big>(</big><em>old</em>, <em>alias</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Join.replace_selectable" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.replace_selectable" title="sqlalchemy.sql.expression.FromClause.replace_selectable"><tt class="xref py py-meth docutils literal"><span class="pre">replace_selectable()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>replace all occurrences of FromClause ‘old’ with the given Alias
object, returning a copy of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Join.select">
<tt class="descname">select</tt><big>(</big><em>whereclause=None</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Join.select" title="Permalink to this definition">¶</a></dt>
<dd><p>Create a <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> from this <a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a>.</p>
<p>The equivalent long-hand form, given a <a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> object
<tt class="docutils literal"><span class="pre">j</span></tt>, is:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="n">select</span>
<span class="n">j</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">j</span><span class="o">.</span><span class="n">left</span><span class="p">,</span> <span class="n">j</span><span class="o">.</span><span class="n">right</span><span class="p">],</span> <span class="o">**</span><span class="n">kw</span><span class="p">)</span><span class="o">.</span>\
<span class="n">where</span><span class="p">(</span><span class="n">whereclause</span><span class="p">)</span><span class="o">.</span>\
<span class="n">select_from</span><span class="p">(</span><span class="n">j</span><span class="p">)</span></pre></div>
</div>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.Join.select.params.whereclause"></span><strong>whereclause</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Join.select.params.whereclause">¶</a> – the WHERE criterion that will be sent to
the <a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a> function</li>
<li><span class="target" id="sqlalchemy.sql.expression.Join.select.params.**kwargs"></span><strong>**kwargs</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Join.select.params.**kwargs">¶</a> – all other kwargs are sent to the
underlying <a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a> function.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Join.unique_params">
<tt class="descname">unique_params</tt><big>(</big><em>*optionaldict</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Join.unique_params" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.unique_params" title="sqlalchemy.sql.expression.ClauseElement.unique_params"><tt class="xref py py-meth docutils literal"><span class="pre">unique_params()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Return a copy with <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.bindparam" title="sqlalchemy.sql.expression.bindparam"><tt class="xref py py-func docutils literal"><span class="pre">bindparam()</span></tt></a> elements replaced.</p>
<p>Same functionality as <tt class="docutils literal"><span class="pre">params()</span></tt>, except adds <cite>unique=True</cite>
to affected bind parameters so that multiple statements can be
used.</p>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.sql.expression.ScalarSelect">
<em class="property">class </em><tt class="descclassname">sqlalchemy.sql.expression.</tt><tt class="descname">ScalarSelect</tt><big>(</big><em>element</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.ScalarSelect" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.sql.expression.Generative</span></tt>, <tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.sql.expression.Grouping</span></tt></p>
<dl class="method">
<dt id="sqlalchemy.sql.expression.ScalarSelect.where">
<tt class="descname">where</tt><big>(</big><em>crit</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.ScalarSelect.where" title="Permalink to this definition">¶</a></dt>
<dd><p>Apply a WHERE clause to the SELECT statement referred to
by this <a class="reference internal" href="#sqlalchemy.sql.expression.ScalarSelect" title="sqlalchemy.sql.expression.ScalarSelect"><tt class="xref py py-class docutils literal"><span class="pre">ScalarSelect</span></tt></a>.</p>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.sql.expression.Select">
<em class="property">class </em><tt class="descclassname">sqlalchemy.sql.expression.</tt><tt class="descname">Select</tt><big>(</big><em>columns=None</em>, <em>whereclause=None</em>, <em>from_obj=None</em>, <em>distinct=False</em>, <em>having=None</em>, <em>correlate=True</em>, <em>prefixes=None</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <a class="reference internal" href="#sqlalchemy.sql.expression.HasPrefixes" title="sqlalchemy.sql.expression.HasPrefixes"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.sql.expression.HasPrefixes</span></tt></a>, <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect" title="sqlalchemy.sql.expression.GenerativeSelect"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.sql.expression.GenerativeSelect</span></tt></a></p>
<p>Represents a <tt class="docutils literal"><span class="pre">SELECT</span></tt> statement.</p>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.__init__">
<tt class="descname">__init__</tt><big>(</big><em>columns=None</em>, <em>whereclause=None</em>, <em>from_obj=None</em>, <em>distinct=False</em>, <em>having=None</em>, <em>correlate=True</em>, <em>prefixes=None</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.__init__" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct a new <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> object.</p>
<p>This constructor is mirrored as a public API function; see <a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a> for a full usage and argument description.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.alias">
<tt class="descname">alias</tt><big>(</big><em>name=None</em>, <em>flat=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.alias" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.alias" title="sqlalchemy.sql.expression.FromClause.alias"><tt class="xref py py-meth docutils literal"><span class="pre">alias()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>return an alias of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<p>This is shorthand for calling:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="n">alias</span>
<span class="n">a</span> <span class="o">=</span> <span class="n">alias</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">name</span><span class="o">=</span><span class="n">name</span><span class="p">)</span></pre></div>
</div>
<p>See <a class="reference internal" href="#sqlalchemy.sql.expression.alias" title="sqlalchemy.sql.expression.alias"><tt class="xref py py-func docutils literal"><span class="pre">alias()</span></tt></a> for details.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.append_column">
<tt class="descname">append_column</tt><big>(</big><em>column</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.append_column" title="Permalink to this definition">¶</a></dt>
<dd><p>append the given column expression to the columns clause of this
select() construct.</p>
<p>This is an <strong>in-place</strong> mutation method; the
<a class="reference internal" href="#sqlalchemy.sql.expression.Select.column" title="sqlalchemy.sql.expression.Select.column"><tt class="xref py py-meth docutils literal"><span class="pre">column()</span></tt></a> method is preferred, as it provides standard
<a class="reference internal" href="../glossary.html#term-method-chaining"><em class="xref std std-term">method chaining</em></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.append_correlation">
<tt class="descname">append_correlation</tt><big>(</big><em>fromclause</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.append_correlation" title="Permalink to this definition">¶</a></dt>
<dd><p>append the given correlation expression to this select()
construct.</p>
<p>This is an <strong>in-place</strong> mutation method; the
<a class="reference internal" href="#sqlalchemy.sql.expression.Select.correlate" title="sqlalchemy.sql.expression.Select.correlate"><tt class="xref py py-meth docutils literal"><span class="pre">correlate()</span></tt></a> method is preferred, as it provides
standard <a class="reference internal" href="../glossary.html#term-method-chaining"><em class="xref std std-term">method chaining</em></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.append_from">
<tt class="descname">append_from</tt><big>(</big><em>fromclause</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.append_from" title="Permalink to this definition">¶</a></dt>
<dd><p>append the given FromClause expression to this select() construct’s
FROM clause.</p>
<p>This is an <strong>in-place</strong> mutation method; the
<a class="reference internal" href="#sqlalchemy.sql.expression.Select.select_from" title="sqlalchemy.sql.expression.Select.select_from"><tt class="xref py py-meth docutils literal"><span class="pre">select_from()</span></tt></a> method is preferred, as it provides
standard <a class="reference internal" href="../glossary.html#term-method-chaining"><em class="xref std std-term">method chaining</em></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.append_group_by">
<tt class="descname">append_group_by</tt><big>(</big><em>*clauses</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.append_group_by" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.append_group_by" title="sqlalchemy.sql.expression.GenerativeSelect.append_group_by"><tt class="xref py py-meth docutils literal"><span class="pre">append_group_by()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect" title="sqlalchemy.sql.expression.GenerativeSelect"><tt class="xref py py-class docutils literal"><span class="pre">GenerativeSelect</span></tt></a></div>
<p>Append the given GROUP BY criterion applied to this selectable.</p>
<p>The criterion will be appended to any pre-existing GROUP BY criterion.</p>
<p>This is an <strong>in-place</strong> mutation method; the
<a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.group_by" title="sqlalchemy.sql.expression.GenerativeSelect.group_by"><tt class="xref py py-meth docutils literal"><span class="pre">group_by()</span></tt></a> method is preferred, as it
provides standard <a class="reference internal" href="../glossary.html#term-method-chaining"><em class="xref std std-term">method chaining</em></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.append_having">
<tt class="descname">append_having</tt><big>(</big><em>having</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.append_having" title="Permalink to this definition">¶</a></dt>
<dd><p>append the given expression to this select() construct’s HAVING
criterion.</p>
<p>The expression will be joined to existing HAVING criterion via AND.</p>
<p>This is an <strong>in-place</strong> mutation method; the
<a class="reference internal" href="#sqlalchemy.sql.expression.Select.having" title="sqlalchemy.sql.expression.Select.having"><tt class="xref py py-meth docutils literal"><span class="pre">having()</span></tt></a> method is preferred, as it provides standard
<a class="reference internal" href="../glossary.html#term-method-chaining"><em class="xref std std-term">method chaining</em></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.append_order_by">
<tt class="descname">append_order_by</tt><big>(</big><em>*clauses</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.append_order_by" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.append_order_by" title="sqlalchemy.sql.expression.GenerativeSelect.append_order_by"><tt class="xref py py-meth docutils literal"><span class="pre">append_order_by()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect" title="sqlalchemy.sql.expression.GenerativeSelect"><tt class="xref py py-class docutils literal"><span class="pre">GenerativeSelect</span></tt></a></div>
<p>Append the given ORDER BY criterion applied to this selectable.</p>
<p>The criterion will be appended to any pre-existing ORDER BY criterion.</p>
<p>This is an <strong>in-place</strong> mutation method; the
<a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.order_by" title="sqlalchemy.sql.expression.GenerativeSelect.order_by"><tt class="xref py py-meth docutils literal"><span class="pre">order_by()</span></tt></a> method is preferred, as it
provides standard <a class="reference internal" href="../glossary.html#term-method-chaining"><em class="xref std std-term">method chaining</em></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.append_prefix">
<tt class="descname">append_prefix</tt><big>(</big><em>clause</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.append_prefix" title="Permalink to this definition">¶</a></dt>
<dd><p>append the given columns clause prefix expression to this select()
construct.</p>
<p>This is an <strong>in-place</strong> mutation method; the
<a class="reference internal" href="#sqlalchemy.sql.expression.Select.prefix_with" title="sqlalchemy.sql.expression.Select.prefix_with"><tt class="xref py py-meth docutils literal"><span class="pre">prefix_with()</span></tt></a> method is preferred, as it provides
standard <a class="reference internal" href="../glossary.html#term-method-chaining"><em class="xref std std-term">method chaining</em></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.append_whereclause">
<tt class="descname">append_whereclause</tt><big>(</big><em>whereclause</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.append_whereclause" title="Permalink to this definition">¶</a></dt>
<dd><p>append the given expression to this select() construct’s WHERE
criterion.</p>
<p>The expression will be joined to existing WHERE criterion via AND.</p>
<p>This is an <strong>in-place</strong> mutation method; the
<a class="reference internal" href="#sqlalchemy.sql.expression.Select.where" title="sqlalchemy.sql.expression.Select.where"><tt class="xref py py-meth docutils literal"><span class="pre">where()</span></tt></a> method is preferred, as it provides standard
<a class="reference internal" href="../glossary.html#term-method-chaining"><em class="xref std std-term">method chaining</em></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.apply_labels">
<tt class="descname">apply_labels</tt><big>(</big><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.apply_labels" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.apply_labels" title="sqlalchemy.sql.expression.GenerativeSelect.apply_labels"><tt class="xref py py-meth docutils literal"><span class="pre">apply_labels()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect" title="sqlalchemy.sql.expression.GenerativeSelect"><tt class="xref py py-class docutils literal"><span class="pre">GenerativeSelect</span></tt></a></div>
<p>return a new selectable with the ‘use_labels’ flag set to True.</p>
<p>This will result in column expressions being generated using labels
against their table name, such as “SELECT somecolumn AS
tablename_somecolumn”. This allows selectables which contain multiple
FROM clauses to produce a unique set of column names regardless of
name conflicts among the individual FROM clauses.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.as_scalar">
<tt class="descname">as_scalar</tt><big>(</big><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.as_scalar" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase.as_scalar" title="sqlalchemy.sql.expression.SelectBase.as_scalar"><tt class="xref py py-meth docutils literal"><span class="pre">as_scalar()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase" title="sqlalchemy.sql.expression.SelectBase"><tt class="xref py py-class docutils literal"><span class="pre">SelectBase</span></tt></a></div>
<p>return a ‘scalar’ representation of this selectable, which can be
used as a column expression.</p>
<p>Typically, a select statement which has only one column in its columns
clause is eligible to be used as a scalar expression.</p>
<p>The returned object is an instance of
<a class="reference internal" href="#sqlalchemy.sql.expression.ScalarSelect" title="sqlalchemy.sql.expression.ScalarSelect"><tt class="xref py py-class docutils literal"><span class="pre">ScalarSelect</span></tt></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.autocommit">
<tt class="descname">autocommit</tt><big>(</big><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.autocommit" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase.autocommit" title="sqlalchemy.sql.expression.SelectBase.autocommit"><tt class="xref py py-meth docutils literal"><span class="pre">autocommit()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase" title="sqlalchemy.sql.expression.SelectBase"><tt class="xref py py-class docutils literal"><span class="pre">SelectBase</span></tt></a></div>
<p>return a new selectable with the ‘autocommit’ flag set to
True.</p>
<div class="deprecated">
<p><span>Deprecated since version 0.6: </span><tt class="docutils literal"><span class="pre">autocommit()</span></tt> is deprecated. Use <a class="reference internal" href="#sqlalchemy.sql.expression.Executable.execution_options" title="sqlalchemy.sql.expression.Executable.execution_options"><tt class="xref py py-meth docutils literal"><span class="pre">Executable.execution_options()</span></tt></a> with the ‘autocommit’ flag.</p>
</div>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.Select.c">
<tt class="descname">c</tt><a class="headerlink" href="#sqlalchemy.sql.expression.Select.c" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.c" title="sqlalchemy.sql.expression.FromClause.c"><tt class="xref py py-attr docutils literal"><span class="pre">c</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>An alias for the <a class="reference internal" href="#sqlalchemy.sql.expression.Select.columns" title="sqlalchemy.sql.expression.Select.columns"><tt class="xref py py-attr docutils literal"><span class="pre">columns</span></tt></a> attribute.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.column">
<tt class="descname">column</tt><big>(</big><em>column</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.column" title="Permalink to this definition">¶</a></dt>
<dd><p>return a new select() construct with the given column expression
added to its columns clause.</p>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.Select.columns">
<tt class="descname">columns</tt><a class="headerlink" href="#sqlalchemy.sql.expression.Select.columns" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.columns" title="sqlalchemy.sql.expression.FromClause.columns"><tt class="xref py py-attr docutils literal"><span class="pre">columns</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>A named-based collection of <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> objects
maintained by this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<p>The <a class="reference internal" href="#sqlalchemy.sql.expression.Select.columns" title="sqlalchemy.sql.expression.Select.columns"><tt class="xref py py-attr docutils literal"><span class="pre">columns</span></tt></a>, or <a class="reference internal" href="#sqlalchemy.sql.expression.Select.c" title="sqlalchemy.sql.expression.Select.c"><tt class="xref py py-attr docutils literal"><span class="pre">c</span></tt></a> collection, is the gateway
to the construction of SQL expressions using table-bound or
other selectable-bound columns:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">select</span><span class="p">([</span><span class="n">mytable</span><span class="p">])</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="n">mytable</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">somecolumn</span> <span class="o">==</span> <span class="mi">5</span><span class="p">)</span></pre></div>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.compare">
<tt class="descname">compare</tt><big>(</big><em>other</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.compare" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.compare" title="sqlalchemy.sql.expression.ClauseElement.compare"><tt class="xref py py-meth docutils literal"><span class="pre">compare()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Compare this ClauseElement to the given ClauseElement.</p>
<p>Subclasses should override the default behavior, which is a
straight identity comparison.</p>
<p>**kw are arguments consumed by subclass compare() methods and
may be used to modify the criteria for comparison.
(see <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a>)</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.compile">
<tt class="descname">compile</tt><big>(</big><em>bind=None</em>, <em>dialect=None</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.compile" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.compile" title="sqlalchemy.sql.expression.ClauseElement.compile"><tt class="xref py py-meth docutils literal"><span class="pre">compile()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Compile this SQL expression.</p>
<p>The return value is a <a class="reference internal" href="internals.html#sqlalchemy.engine.interfaces.Compiled" title="sqlalchemy.engine.interfaces.Compiled"><tt class="xref py py-class docutils literal"><span class="pre">Compiled</span></tt></a> object.
Calling <tt class="docutils literal"><span class="pre">str()</span></tt> or <tt class="docutils literal"><span class="pre">unicode()</span></tt> on the returned value will yield a
string representation of the result. The
<a class="reference internal" href="internals.html#sqlalchemy.engine.interfaces.Compiled" title="sqlalchemy.engine.interfaces.Compiled"><tt class="xref py py-class docutils literal"><span class="pre">Compiled</span></tt></a> object also can return a
dictionary of bind parameter names and values
using the <tt class="docutils literal"><span class="pre">params</span></tt> accessor.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.Select.compile.params.bind"></span><strong>bind</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Select.compile.params.bind">¶</a> – An <tt class="docutils literal"><span class="pre">Engine</span></tt> or <tt class="docutils literal"><span class="pre">Connection</span></tt> from which a
<tt class="docutils literal"><span class="pre">Compiled</span></tt> will be acquired. This argument takes precedence over
this <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a>‘s bound engine, if any.</li>
<li><span class="target" id="sqlalchemy.sql.expression.Select.compile.params.column_keys"></span><strong>column_keys</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Select.compile.params.column_keys">¶</a> – Used for INSERT and UPDATE statements, a list of
column names which should be present in the VALUES clause of the
compiled statement. If <tt class="docutils literal"><span class="pre">None</span></tt>, all columns from the target table
object are rendered.</li>
<li><span class="target" id="sqlalchemy.sql.expression.Select.compile.params.dialect"></span><strong>dialect</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Select.compile.params.dialect">¶</a> – A <tt class="docutils literal"><span class="pre">Dialect</span></tt> instance from which a <tt class="docutils literal"><span class="pre">Compiled</span></tt>
will be acquired. This argument takes precedence over the <cite>bind</cite>
argument as well as this <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a>‘s bound engine,
if any.</li>
<li><span class="target" id="sqlalchemy.sql.expression.Select.compile.params.inline"></span><strong>inline</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Select.compile.params.inline">¶</a> – Used for INSERT statements, for a dialect which does
not support inline retrieval of newly generated primary key
columns, will force the expression used to create the new primary
key value to be rendered inline within the INSERT statement’s
VALUES clause. This typically refers to Sequence execution but may
also refer to any server-side default generation function
associated with a primary key <cite>Column</cite>.</li>
<li><span class="target" id="sqlalchemy.sql.expression.Select.compile.params.compile_kwargs"></span><strong>compile_kwargs</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Select.compile.params.compile_kwargs">¶</a> – <p>optional dictionary of additional parameters
that will be passed through to the compiler within all “visit”
methods. This allows any custom flag to be passed through to
a custom compilation construct, for example. It is also used
for the case of passing the <tt class="docutils literal"><span class="pre">literal_binds</span></tt> flag through:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy.sql</span> <span class="kn">import</span> <span class="n">table</span><span class="p">,</span> <span class="n">column</span><span class="p">,</span> <span class="n">select</span>
<span class="n">t</span> <span class="o">=</span> <span class="n">table</span><span class="p">(</span><span class="s">'t'</span><span class="p">,</span> <span class="n">column</span><span class="p">(</span><span class="s">'x'</span><span class="p">))</span>
<span class="n">s</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">t</span><span class="p">])</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="n">t</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">x</span> <span class="o">==</span> <span class="mi">5</span><span class="p">)</span>
<span class="k">print</span> <span class="n">s</span><span class="o">.</span><span class="n">compile</span><span class="p">(</span><span class="n">compile_kwargs</span><span class="o">=</span><span class="p">{</span><span class="s">"literal_binds"</span><span class="p">:</span> <span class="bp">True</span><span class="p">})</span></pre></div>
</div>
<div class="versionadded">
<p><span>New in version 0.9.0.</span></p>
</div>
</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="../faq.html#faq-sql-expression-string"><em>How do I render SQL expressions as strings, possibly with bound parameters inlined?</em></a></p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.correlate">
<tt class="descname">correlate</tt><big>(</big><em>*fromclauses</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.correlate" title="Permalink to this definition">¶</a></dt>
<dd><p>return a new <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> which will correlate the given FROM
clauses to that of an enclosing <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a>.</p>
<p>Calling this method turns off the <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> object’s
default behavior of “auto-correlation”. Normally, FROM elements
which appear in a <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> that encloses this one via
its <a class="reference internal" href="../glossary.html#term-where-clause"><em class="xref std std-term">WHERE clause</em></a>, ORDER BY, HAVING or
<a class="reference internal" href="../glossary.html#term-columns-clause"><em class="xref std std-term">columns clause</em></a> will be omitted from this <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a>
object’s <a class="reference internal" href="../glossary.html#term-from-clause"><em class="xref std std-term">FROM clause</em></a>.
Setting an explicit correlation collection using the
<a class="reference internal" href="#sqlalchemy.sql.expression.Select.correlate" title="sqlalchemy.sql.expression.Select.correlate"><tt class="xref py py-meth docutils literal"><span class="pre">Select.correlate()</span></tt></a> method provides a fixed list of FROM objects
that can potentially take place in this process.</p>
<p>When <a class="reference internal" href="#sqlalchemy.sql.expression.Select.correlate" title="sqlalchemy.sql.expression.Select.correlate"><tt class="xref py py-meth docutils literal"><span class="pre">Select.correlate()</span></tt></a> is used to apply specific FROM clauses
for correlation, the FROM elements become candidates for
correlation regardless of how deeply nested this <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a>
object is, relative to an enclosing <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> which refers to
the same FROM object. This is in contrast to the behavior of
“auto-correlation” which only correlates to an immediate enclosing
<a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a>. Multi-level correlation ensures that the link
between enclosed and enclosing <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> is always via
at least one WHERE/ORDER BY/HAVING/columns clause in order for
correlation to take place.</p>
<p>If <tt class="docutils literal"><span class="pre">None</span></tt> is passed, the <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> object will correlate
none of its FROM entries, and all will render unconditionally
in the local FROM clause.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><span class="target" id="sqlalchemy.sql.expression.Select.correlate.params.*fromclauses"></span><strong>*fromclauses</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Select.correlate.params.*fromclauses">¶</a> – <p>a list of one or more <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>
constructs, or other compatible constructs (i.e. ORM-mapped
classes) to become part of the correlate collection.</p>
<div class="versionchanged">
<p><span>Changed in version 0.8.0: </span>ORM-mapped classes are accepted by
<a class="reference internal" href="#sqlalchemy.sql.expression.Select.correlate" title="sqlalchemy.sql.expression.Select.correlate"><tt class="xref py py-meth docutils literal"><span class="pre">Select.correlate()</span></tt></a>.</p>
</div>
</td>
</tr>
</tbody>
</table>
<div class="versionchanged">
<p><span>Changed in version 0.8.0: </span>The <a class="reference internal" href="#sqlalchemy.sql.expression.Select.correlate" title="sqlalchemy.sql.expression.Select.correlate"><tt class="xref py py-meth docutils literal"><span class="pre">Select.correlate()</span></tt></a> method no
longer unconditionally removes entries from the FROM clause;
instead, the candidate FROM entries must also be matched by a FROM
entry located in an enclosing <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a>, which ultimately
encloses this one as present in the WHERE clause, ORDER BY clause,
HAVING clause, or columns clause of an enclosing <tt class="xref py py-meth docutils literal"><span class="pre">Select()</span></tt>.</p>
</div>
<div class="versionchanged">
<p><span>Changed in version 0.8.2: </span>explicit correlation takes place
via any level of nesting of <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> objects; in previous
0.8 versions, correlation would only occur relative to the
immediate enclosing <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> construct.</p>
</div>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p><a class="reference internal" href="#sqlalchemy.sql.expression.Select.correlate_except" title="sqlalchemy.sql.expression.Select.correlate_except"><tt class="xref py py-meth docutils literal"><span class="pre">Select.correlate_except()</span></tt></a></p>
<p class="last"><a class="reference internal" href="tutorial.html#correlated-subqueries"><em>Correlated Subqueries</em></a></p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.correlate_except">
<tt class="descname">correlate_except</tt><big>(</big><em>*fromclauses</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.correlate_except" title="Permalink to this definition">¶</a></dt>
<dd><p>return a new <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> which will omit the given FROM
clauses from the auto-correlation process.</p>
<p>Calling <a class="reference internal" href="#sqlalchemy.sql.expression.Select.correlate_except" title="sqlalchemy.sql.expression.Select.correlate_except"><tt class="xref py py-meth docutils literal"><span class="pre">Select.correlate_except()</span></tt></a> turns off the
<a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> object’s default behavior of
“auto-correlation” for the given FROM elements. An element
specified here will unconditionally appear in the FROM list, while
all other FROM elements remain subject to normal auto-correlation
behaviors.</p>
<div class="versionchanged">
<p><span>Changed in version 0.8.2: </span>The <a class="reference internal" href="#sqlalchemy.sql.expression.Select.correlate_except" title="sqlalchemy.sql.expression.Select.correlate_except"><tt class="xref py py-meth docutils literal"><span class="pre">Select.correlate_except()</span></tt></a>
method was improved to fully prevent FROM clauses specified here
from being omitted from the immediate FROM clause of this
<a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a>.</p>
</div>
<p>If <tt class="docutils literal"><span class="pre">None</span></tt> is passed, the <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a> object will correlate
all of its FROM entries.</p>
<div class="versionchanged">
<p><span>Changed in version 0.8.2: </span>calling <tt class="docutils literal"><span class="pre">correlate_except(None)</span></tt> will
correctly auto-correlate all FROM clauses.</p>
</div>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><span class="target" id="sqlalchemy.sql.expression.Select.correlate_except.params.*fromclauses"></span><strong>*fromclauses</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Select.correlate_except.params.*fromclauses">¶</a> – a list of one or more <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>
constructs, or other compatible constructs (i.e. ORM-mapped
classes) to become part of the correlate-exception collection.</td>
</tr>
</tbody>
</table>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p><a class="reference internal" href="#sqlalchemy.sql.expression.Select.correlate" title="sqlalchemy.sql.expression.Select.correlate"><tt class="xref py py-meth docutils literal"><span class="pre">Select.correlate()</span></tt></a></p>
<p class="last"><a class="reference internal" href="tutorial.html#correlated-subqueries"><em>Correlated Subqueries</em></a></p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.correspond_on_equivalents">
<tt class="descname">correspond_on_equivalents</tt><big>(</big><em>column</em>, <em>equivalents</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.correspond_on_equivalents" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.correspond_on_equivalents" title="sqlalchemy.sql.expression.FromClause.correspond_on_equivalents"><tt class="xref py py-meth docutils literal"><span class="pre">correspond_on_equivalents()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return corresponding_column for the given column, or if None
search for a match in the given dictionary.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.corresponding_column">
<tt class="descname">corresponding_column</tt><big>(</big><em>column</em>, <em>require_embedded=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.corresponding_column" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.corresponding_column" title="sqlalchemy.sql.expression.FromClause.corresponding_column"><tt class="xref py py-meth docutils literal"><span class="pre">corresponding_column()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Given a <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a>, return the exported
<a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> object from this <a class="reference internal" href="#sqlalchemy.sql.expression.Selectable" title="sqlalchemy.sql.expression.Selectable"><tt class="xref py py-class docutils literal"><span class="pre">Selectable</span></tt></a>
which corresponds to that original
<a class="reference internal" href="metadata.html#sqlalchemy.schema.Column" title="sqlalchemy.schema.Column"><tt class="xref py py-class docutils literal"><span class="pre">Column</span></tt></a> via a common ancestor
column.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.Select.corresponding_column.params.column"></span><strong>column</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Select.corresponding_column.params.column">¶</a> – the target <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> to be matched</li>
<li><span class="target" id="sqlalchemy.sql.expression.Select.corresponding_column.params.require_embedded"></span><strong>require_embedded</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Select.corresponding_column.params.require_embedded">¶</a> – only return corresponding columns for
the given <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a>, if the given
<a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> is actually present within a sub-element
of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>. Normally the column will match if
it merely shares a common ancestor with one of the exported
columns of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.count">
<tt class="descname">count</tt><big>(</big><em>whereclause=None</em>, <em>**params</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.count" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.count" title="sqlalchemy.sql.expression.FromClause.count"><tt class="xref py py-meth docutils literal"><span class="pre">count()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>return a SELECT COUNT generated against this
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.cte">
<tt class="descname">cte</tt><big>(</big><em>name=None</em>, <em>recursive=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.cte" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase.cte" title="sqlalchemy.sql.expression.SelectBase.cte"><tt class="xref py py-meth docutils literal"><span class="pre">cte()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase" title="sqlalchemy.sql.expression.SelectBase"><tt class="xref py py-class docutils literal"><span class="pre">SelectBase</span></tt></a></div>
<p>Return a new <a class="reference internal" href="#sqlalchemy.sql.expression.CTE" title="sqlalchemy.sql.expression.CTE"><tt class="xref py py-class docutils literal"><span class="pre">CTE</span></tt></a>, or Common Table Expression instance.</p>
<p>Common table expressions are a SQL standard whereby SELECT
statements can draw upon secondary statements specified along
with the primary statement, using a clause called “WITH”.
Special semantics regarding UNION can also be employed to
allow “recursive” queries, where a SELECT statement can draw
upon the set of rows that have previously been selected.</p>
<p>SQLAlchemy detects <a class="reference internal" href="#sqlalchemy.sql.expression.CTE" title="sqlalchemy.sql.expression.CTE"><tt class="xref py py-class docutils literal"><span class="pre">CTE</span></tt></a> objects, which are treated
similarly to <a class="reference internal" href="#sqlalchemy.sql.expression.Alias" title="sqlalchemy.sql.expression.Alias"><tt class="xref py py-class docutils literal"><span class="pre">Alias</span></tt></a> objects, as special elements
to be delivered to the FROM clause of the statement as well
as to a WITH clause at the top of the statement.</p>
<div class="versionadded">
<p><span>New in version 0.7.6.</span></p>
</div>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.Select.cte.params.name"></span><strong>name</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Select.cte.params.name">¶</a> – name given to the common table expression. Like
<tt class="xref py py-meth docutils literal"><span class="pre">_FromClause.alias()</span></tt>, the name can be left as <tt class="docutils literal"><span class="pre">None</span></tt>
in which case an anonymous symbol will be used at query
compile time.</li>
<li><span class="target" id="sqlalchemy.sql.expression.Select.cte.params.recursive"></span><strong>recursive</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Select.cte.params.recursive">¶</a> – if <tt class="docutils literal"><span class="pre">True</span></tt>, will render <tt class="docutils literal"><span class="pre">WITH</span> <span class="pre">RECURSIVE</span></tt>.
A recursive common table expression is intended to be used in
conjunction with UNION ALL in order to derive rows
from those already selected.</li>
</ul>
</td>
</tr>
</tbody>
</table>
<p>The following examples illustrate two examples from
Postgresql’s documentation at
<a class="reference external" href="http://www.postgresql.org/docs/8.4/static/queries-with.html">http://www.postgresql.org/docs/8.4/static/queries-with.html</a>.</p>
<p>Example 1, non recursive:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="p">(</span><span class="n">Table</span><span class="p">,</span> <span class="n">Column</span><span class="p">,</span> <span class="n">String</span><span class="p">,</span> <span class="n">Integer</span><span class="p">,</span>
<span class="n">MetaData</span><span class="p">,</span> <span class="n">select</span><span class="p">,</span> <span class="n">func</span><span class="p">)</span>
<span class="n">metadata</span> <span class="o">=</span> <span class="n">MetaData</span><span class="p">()</span>
<span class="n">orders</span> <span class="o">=</span> <span class="n">Table</span><span class="p">(</span><span class="s">'orders'</span><span class="p">,</span> <span class="n">metadata</span><span class="p">,</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'region'</span><span class="p">,</span> <span class="n">String</span><span class="p">),</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'amount'</span><span class="p">,</span> <span class="n">Integer</span><span class="p">),</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'product'</span><span class="p">,</span> <span class="n">String</span><span class="p">),</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'quantity'</span><span class="p">,</span> <span class="n">Integer</span><span class="p">)</span>
<span class="p">)</span>
<span class="n">regional_sales</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span>
<span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">region</span><span class="p">,</span>
<span class="n">func</span><span class="o">.</span><span class="n">sum</span><span class="p">(</span><span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">amount</span><span class="p">)</span><span class="o">.</span><span class="n">label</span><span class="p">(</span><span class="s">'total_sales'</span><span class="p">)</span>
<span class="p">])</span><span class="o">.</span><span class="n">group_by</span><span class="p">(</span><span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">region</span><span class="p">)</span><span class="o">.</span><span class="n">cte</span><span class="p">(</span><span class="s">"regional_sales"</span><span class="p">)</span>
<span class="n">top_regions</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">regional_sales</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">region</span><span class="p">])</span><span class="o">.</span>\
<span class="n">where</span><span class="p">(</span>
<span class="n">regional_sales</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">total_sales</span> <span class="o">></span>
<span class="n">select</span><span class="p">([</span>
<span class="n">func</span><span class="o">.</span><span class="n">sum</span><span class="p">(</span><span class="n">regional_sales</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">total_sales</span><span class="p">)</span><span class="o">/</span><span class="mi">10</span>
<span class="p">])</span>
<span class="p">)</span><span class="o">.</span><span class="n">cte</span><span class="p">(</span><span class="s">"top_regions"</span><span class="p">)</span>
<span class="n">statement</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span>
<span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">region</span><span class="p">,</span>
<span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">product</span><span class="p">,</span>
<span class="n">func</span><span class="o">.</span><span class="n">sum</span><span class="p">(</span><span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">quantity</span><span class="p">)</span><span class="o">.</span><span class="n">label</span><span class="p">(</span><span class="s">"product_units"</span><span class="p">),</span>
<span class="n">func</span><span class="o">.</span><span class="n">sum</span><span class="p">(</span><span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">amount</span><span class="p">)</span><span class="o">.</span><span class="n">label</span><span class="p">(</span><span class="s">"product_sales"</span><span class="p">)</span>
<span class="p">])</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">region</span><span class="o">.</span><span class="n">in_</span><span class="p">(</span>
<span class="n">select</span><span class="p">([</span><span class="n">top_regions</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">region</span><span class="p">])</span>
<span class="p">))</span><span class="o">.</span><span class="n">group_by</span><span class="p">(</span><span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">region</span><span class="p">,</span> <span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">product</span><span class="p">)</span>
<span class="n">result</span> <span class="o">=</span> <span class="n">conn</span><span class="o">.</span><span class="n">execute</span><span class="p">(</span><span class="n">statement</span><span class="p">)</span><span class="o">.</span><span class="n">fetchall</span><span class="p">()</span></pre></div>
</div>
<p>Example 2, WITH RECURSIVE:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="p">(</span><span class="n">Table</span><span class="p">,</span> <span class="n">Column</span><span class="p">,</span> <span class="n">String</span><span class="p">,</span> <span class="n">Integer</span><span class="p">,</span>
<span class="n">MetaData</span><span class="p">,</span> <span class="n">select</span><span class="p">,</span> <span class="n">func</span><span class="p">)</span>
<span class="n">metadata</span> <span class="o">=</span> <span class="n">MetaData</span><span class="p">()</span>
<span class="n">parts</span> <span class="o">=</span> <span class="n">Table</span><span class="p">(</span><span class="s">'parts'</span><span class="p">,</span> <span class="n">metadata</span><span class="p">,</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'part'</span><span class="p">,</span> <span class="n">String</span><span class="p">),</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'sub_part'</span><span class="p">,</span> <span class="n">String</span><span class="p">),</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'quantity'</span><span class="p">,</span> <span class="n">Integer</span><span class="p">),</span>
<span class="p">)</span>
<span class="n">included_parts</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span>
<span class="n">parts</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">sub_part</span><span class="p">,</span>
<span class="n">parts</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">part</span><span class="p">,</span>
<span class="n">parts</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">quantity</span><span class="p">])</span><span class="o">.</span>\
<span class="n">where</span><span class="p">(</span><span class="n">parts</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">part</span><span class="o">==</span><span class="s">'our part'</span><span class="p">)</span><span class="o">.</span>\
<span class="n">cte</span><span class="p">(</span><span class="n">recursive</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span>
<span class="n">incl_alias</span> <span class="o">=</span> <span class="n">included_parts</span><span class="o">.</span><span class="n">alias</span><span class="p">()</span>
<span class="n">parts_alias</span> <span class="o">=</span> <span class="n">parts</span><span class="o">.</span><span class="n">alias</span><span class="p">()</span>
<span class="n">included_parts</span> <span class="o">=</span> <span class="n">included_parts</span><span class="o">.</span><span class="n">union_all</span><span class="p">(</span>
<span class="n">select</span><span class="p">([</span>
<span class="n">parts_alias</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">sub_part</span><span class="p">,</span>
<span class="n">parts_alias</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">part</span><span class="p">,</span>
<span class="n">parts_alias</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">quantity</span>
<span class="p">])</span><span class="o">.</span>
<span class="n">where</span><span class="p">(</span><span class="n">parts_alias</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">part</span><span class="o">==</span><span class="n">incl_alias</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">sub_part</span><span class="p">)</span>
<span class="p">)</span>
<span class="n">statement</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span>
<span class="n">included_parts</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">sub_part</span><span class="p">,</span>
<span class="n">func</span><span class="o">.</span><span class="n">sum</span><span class="p">(</span><span class="n">included_parts</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">quantity</span><span class="p">)</span><span class="o">.</span>
<span class="n">label</span><span class="p">(</span><span class="s">'total_quantity'</span><span class="p">)</span>
<span class="p">])</span><span class="o">.</span>\
<span class="n">group_by</span><span class="p">(</span><span class="n">included_parts</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">sub_part</span><span class="p">)</span>
<span class="n">result</span> <span class="o">=</span> <span class="n">conn</span><span class="o">.</span><span class="n">execute</span><span class="p">(</span><span class="n">statement</span><span class="p">)</span><span class="o">.</span><span class="n">fetchall</span><span class="p">()</span></pre></div>
</div>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="../orm/query.html#sqlalchemy.orm.query.Query.cte" title="sqlalchemy.orm.query.Query.cte"><tt class="xref py py-meth docutils literal"><span class="pre">orm.query.Query.cte()</span></tt></a> - ORM version of
<a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase.cte" title="sqlalchemy.sql.expression.SelectBase.cte"><tt class="xref py py-meth docutils literal"><span class="pre">SelectBase.cte()</span></tt></a>.</p>
</div>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.Select.description">
<tt class="descname">description</tt><a class="headerlink" href="#sqlalchemy.sql.expression.Select.description" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.description" title="sqlalchemy.sql.expression.FromClause.description"><tt class="xref py py-attr docutils literal"><span class="pre">description</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>a brief description of this FromClause.</p>
<p>Used primarily for error message formatting.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.distinct">
<tt class="descname">distinct</tt><big>(</big><em>*expr</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.distinct" title="Permalink to this definition">¶</a></dt>
<dd><p>Return a new select() construct which will apply DISTINCT to its
columns clause.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><span class="target" id="sqlalchemy.sql.expression.Select.distinct.params.*expr"></span><strong>*expr</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Select.distinct.params.*expr">¶</a> – optional column expressions. When present,
the Postgresql dialect will render a <tt class="docutils literal"><span class="pre">DISTINCT</span> <span class="pre">ON</span> <span class="pre">(<expressions>>)</span></tt>
construct.</td>
</tr>
</tbody>
</table>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.except_">
<tt class="descname">except_</tt><big>(</big><em>other</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.except_" title="Permalink to this definition">¶</a></dt>
<dd><p>return a SQL EXCEPT of this select() construct against the given
selectable.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.except_all">
<tt class="descname">except_all</tt><big>(</big><em>other</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.except_all" title="Permalink to this definition">¶</a></dt>
<dd><p>return a SQL EXCEPT ALL of this select() construct against the
given selectable.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.execute">
<tt class="descname">execute</tt><big>(</big><em>*multiparams</em>, <em>**params</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.execute" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.Executable.execute" title="sqlalchemy.sql.expression.Executable.execute"><tt class="xref py py-meth docutils literal"><span class="pre">execute()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.Executable" title="sqlalchemy.sql.expression.Executable"><tt class="xref py py-class docutils literal"><span class="pre">Executable</span></tt></a></div>
<p>Compile and execute this <a class="reference internal" href="#sqlalchemy.sql.expression.Executable" title="sqlalchemy.sql.expression.Executable"><tt class="xref py py-class docutils literal"><span class="pre">Executable</span></tt></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.execution_options">
<tt class="descname">execution_options</tt><big>(</big><em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.execution_options" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.Executable.execution_options" title="sqlalchemy.sql.expression.Executable.execution_options"><tt class="xref py py-meth docutils literal"><span class="pre">execution_options()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.Executable" title="sqlalchemy.sql.expression.Executable"><tt class="xref py py-class docutils literal"><span class="pre">Executable</span></tt></a></div>
<p>Set non-SQL options for the statement which take effect during
execution.</p>
<p>Execution options can be set on a per-statement or
per <a class="reference internal" href="connections.html#sqlalchemy.engine.Connection" title="sqlalchemy.engine.Connection"><tt class="xref py py-class docutils literal"><span class="pre">Connection</span></tt></a> basis. Additionally, the
<a class="reference internal" href="connections.html#sqlalchemy.engine.Engine" title="sqlalchemy.engine.Engine"><tt class="xref py py-class docutils literal"><span class="pre">Engine</span></tt></a> and ORM <a class="reference internal" href="../orm/query.html#sqlalchemy.orm.query.Query" title="sqlalchemy.orm.query.Query"><tt class="xref py py-class docutils literal"><span class="pre">Query</span></tt></a> objects provide
access to execution options which they in turn configure upon
connections.</p>
<p>The <a class="reference internal" href="#sqlalchemy.sql.expression.Select.execution_options" title="sqlalchemy.sql.expression.Select.execution_options"><tt class="xref py py-meth docutils literal"><span class="pre">execution_options()</span></tt></a> method is generative. A new
instance of this statement is returned that contains the options:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">statement</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">x</span><span class="p">,</span> <span class="n">table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">y</span><span class="p">])</span>
<span class="n">statement</span> <span class="o">=</span> <span class="n">statement</span><span class="o">.</span><span class="n">execution_options</span><span class="p">(</span><span class="n">autocommit</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span></pre></div>
</div>
<p>Note that only a subset of possible execution options can be applied
to a statement - these include “autocommit” and “stream_results”,
but not “isolation_level” or “compiled_cache”.
See <a class="reference internal" href="connections.html#sqlalchemy.engine.Connection.execution_options" title="sqlalchemy.engine.Connection.execution_options"><tt class="xref py py-meth docutils literal"><span class="pre">Connection.execution_options()</span></tt></a> for a full list of
possible options.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p><a class="reference internal" href="connections.html#sqlalchemy.engine.Connection.execution_options" title="sqlalchemy.engine.Connection.execution_options"><tt class="xref py py-meth docutils literal"><span class="pre">Connection.execution_options()</span></tt></a></p>
<p class="last"><a class="reference internal" href="../orm/query.html#sqlalchemy.orm.query.Query.execution_options" title="sqlalchemy.orm.query.Query.execution_options"><tt class="xref py py-meth docutils literal"><span class="pre">Query.execution_options()</span></tt></a></p>
</div>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.Select.for_update">
<tt class="descname">for_update</tt><a class="headerlink" href="#sqlalchemy.sql.expression.Select.for_update" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.for_update" title="sqlalchemy.sql.expression.GenerativeSelect.for_update"><tt class="xref py py-attr docutils literal"><span class="pre">for_update</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect" title="sqlalchemy.sql.expression.GenerativeSelect"><tt class="xref py py-class docutils literal"><span class="pre">GenerativeSelect</span></tt></a></div>
<p>Provide legacy dialect support for the <tt class="docutils literal"><span class="pre">for_update</span></tt> attribute.</p>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.Select.foreign_keys">
<tt class="descname">foreign_keys</tt><a class="headerlink" href="#sqlalchemy.sql.expression.Select.foreign_keys" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.foreign_keys" title="sqlalchemy.sql.expression.FromClause.foreign_keys"><tt class="xref py py-attr docutils literal"><span class="pre">foreign_keys</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return the collection of ForeignKey objects which this
FromClause references.</p>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.Select.froms">
<tt class="descname">froms</tt><a class="headerlink" href="#sqlalchemy.sql.expression.Select.froms" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the displayed list of FromClause elements.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.get_children">
<tt class="descname">get_children</tt><big>(</big><em>column_collections=True</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.get_children" title="Permalink to this definition">¶</a></dt>
<dd><p>return child elements as per the ClauseElement specification.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.group_by">
<tt class="descname">group_by</tt><big>(</big><em>*clauses</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.group_by" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.group_by" title="sqlalchemy.sql.expression.GenerativeSelect.group_by"><tt class="xref py py-meth docutils literal"><span class="pre">group_by()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect" title="sqlalchemy.sql.expression.GenerativeSelect"><tt class="xref py py-class docutils literal"><span class="pre">GenerativeSelect</span></tt></a></div>
<p>return a new selectable with the given list of GROUP BY
criterion applied.</p>
<p>The criterion will be appended to any pre-existing GROUP BY
criterion.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.having">
<tt class="descname">having</tt><big>(</big><em>having</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.having" title="Permalink to this definition">¶</a></dt>
<dd><p>return a new select() construct with the given expression added to
its HAVING clause, joined to the existing clause via AND, if any.</p>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.Select.inner_columns">
<tt class="descname">inner_columns</tt><a class="headerlink" href="#sqlalchemy.sql.expression.Select.inner_columns" title="Permalink to this definition">¶</a></dt>
<dd><p>an iterator of all ColumnElement expressions which would
be rendered into the columns clause of the resulting SELECT statement.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.intersect">
<tt class="descname">intersect</tt><big>(</big><em>other</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.intersect" title="Permalink to this definition">¶</a></dt>
<dd><p>return a SQL INTERSECT of this select() construct against the given
selectable.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.intersect_all">
<tt class="descname">intersect_all</tt><big>(</big><em>other</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.intersect_all" title="Permalink to this definition">¶</a></dt>
<dd><p>return a SQL INTERSECT ALL of this select() construct against the
given selectable.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.join">
<tt class="descname">join</tt><big>(</big><em>right</em>, <em>onclause=None</em>, <em>isouter=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.join" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">join()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return a <a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> from this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>
to another <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<p>E.g.:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="n">join</span>
<span class="n">j</span> <span class="o">=</span> <span class="n">user_table</span><span class="o">.</span><span class="n">join</span><span class="p">(</span><span class="n">address_table</span><span class="p">,</span>
<span class="n">user_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span> <span class="o">==</span> <span class="n">address_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">user_id</span><span class="p">)</span>
<span class="n">stmt</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">user_table</span><span class="p">])</span><span class="o">.</span><span class="n">select_from</span><span class="p">(</span><span class="n">j</span><span class="p">)</span></pre></div>
</div>
<p>would emit SQL along the lines of:</p>
<div class="highlight-python"><pre>SELECT user.id, user.name FROM user
JOIN address ON user.id = address.user_id</pre>
</div>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.Select.join.params.right"></span><strong>right</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Select.join.params.right">¶</a> – the right side of the join; this is any
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> object such as a <a class="reference internal" href="metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a> object, and
may also be a selectable-compatible object such as an ORM-mapped
class.</li>
<li><span class="target" id="sqlalchemy.sql.expression.Select.join.params.onclause"></span><strong>onclause</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Select.join.params.onclause">¶</a> – a SQL expression representing the ON clause of the
join. If left at <tt class="docutils literal"><span class="pre">None</span></tt>, <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a> will attempt to
join the two tables based on a foreign key relationship.</li>
<li><span class="target" id="sqlalchemy.sql.expression.Select.join.params.isouter"></span><strong>isouter</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Select.join.params.isouter">¶</a> – if True, render a LEFT OUTER JOIN, instead of JOIN.</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p><a class="reference internal" href="#sqlalchemy.sql.expression.join" title="sqlalchemy.sql.expression.join"><tt class="xref py py-func docutils literal"><span class="pre">join()</span></tt></a> - standalone function</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> - the type of object produced</p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.label">
<tt class="descname">label</tt><big>(</big><em>name</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.label" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase.label" title="sqlalchemy.sql.expression.SelectBase.label"><tt class="xref py py-meth docutils literal"><span class="pre">label()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase" title="sqlalchemy.sql.expression.SelectBase"><tt class="xref py py-class docutils literal"><span class="pre">SelectBase</span></tt></a></div>
<p>return a ‘scalar’ representation of this selectable, embedded as a
subquery with a label.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase.as_scalar" title="sqlalchemy.sql.expression.SelectBase.as_scalar"><tt class="xref py py-meth docutils literal"><span class="pre">as_scalar()</span></tt></a>.</p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.limit">
<tt class="descname">limit</tt><big>(</big><em>limit</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.limit" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.limit" title="sqlalchemy.sql.expression.GenerativeSelect.limit"><tt class="xref py py-meth docutils literal"><span class="pre">limit()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect" title="sqlalchemy.sql.expression.GenerativeSelect"><tt class="xref py py-class docutils literal"><span class="pre">GenerativeSelect</span></tt></a></div>
<p>return a new selectable with the given LIMIT criterion
applied.</p>
<p>This is a numerical value which usually renders as a <tt class="docutils literal"><span class="pre">LIMIT</span></tt>
expression in the resulting select. Backends that don’t
support <tt class="docutils literal"><span class="pre">LIMIT</span></tt> will attempt to provide similar
functionality.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><span class="target" id="sqlalchemy.sql.expression.Select.limit.params.limit"></span><strong>limit</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Select.limit.params.limit">¶</a> – an integer LIMIT parameter.</td>
</tr>
</tbody>
</table>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.Select.locate_all_froms">
<tt class="descname">locate_all_froms</tt><a class="headerlink" href="#sqlalchemy.sql.expression.Select.locate_all_froms" title="Permalink to this definition">¶</a></dt>
<dd><p>return a Set of all FromClause elements referenced by this Select.</p>
<p>This set is a superset of that returned by the <tt class="docutils literal"><span class="pre">froms</span></tt> property,
which is specifically for those FromClause elements that would
actually be rendered.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.offset">
<tt class="descname">offset</tt><big>(</big><em>offset</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.offset" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.offset" title="sqlalchemy.sql.expression.GenerativeSelect.offset"><tt class="xref py py-meth docutils literal"><span class="pre">offset()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect" title="sqlalchemy.sql.expression.GenerativeSelect"><tt class="xref py py-class docutils literal"><span class="pre">GenerativeSelect</span></tt></a></div>
<p>return a new selectable with the given OFFSET criterion
applied.</p>
<p>This is a numeric value which usually renders as an <tt class="docutils literal"><span class="pre">OFFSET</span></tt>
expression in the resulting select. Backends that don’t
support <tt class="docutils literal"><span class="pre">OFFSET</span></tt> will attempt to provide similar
functionality.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><span class="target" id="sqlalchemy.sql.expression.Select.offset.params.offset"></span><strong>offset</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Select.offset.params.offset">¶</a> – an integer OFFSET parameter.</td>
</tr>
</tbody>
</table>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.order_by">
<tt class="descname">order_by</tt><big>(</big><em>*clauses</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.order_by" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.order_by" title="sqlalchemy.sql.expression.GenerativeSelect.order_by"><tt class="xref py py-meth docutils literal"><span class="pre">order_by()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect" title="sqlalchemy.sql.expression.GenerativeSelect"><tt class="xref py py-class docutils literal"><span class="pre">GenerativeSelect</span></tt></a></div>
<p>return a new selectable with the given list of ORDER BY
criterion applied.</p>
<p>The criterion will be appended to any pre-existing ORDER BY
criterion.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.outerjoin">
<tt class="descname">outerjoin</tt><big>(</big><em>right</em>, <em>onclause=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.outerjoin" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.outerjoin" title="sqlalchemy.sql.expression.FromClause.outerjoin"><tt class="xref py py-meth docutils literal"><span class="pre">outerjoin()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return a <a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> from this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>
to another <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>, with the “isouter” flag set to
True.</p>
<p>E.g.:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="n">outerjoin</span>
<span class="n">j</span> <span class="o">=</span> <span class="n">user_table</span><span class="o">.</span><span class="n">outerjoin</span><span class="p">(</span><span class="n">address_table</span><span class="p">,</span>
<span class="n">user_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span> <span class="o">==</span> <span class="n">address_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">user_id</span><span class="p">)</span></pre></div>
</div>
<p>The above is equivalent to:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">j</span> <span class="o">=</span> <span class="n">user_table</span><span class="o">.</span><span class="n">join</span><span class="p">(</span>
<span class="n">address_table</span><span class="p">,</span>
<span class="n">user_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span> <span class="o">==</span> <span class="n">address_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">user_id</span><span class="p">,</span>
<span class="n">isouter</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span></pre></div>
</div>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.Select.outerjoin.params.right"></span><strong>right</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Select.outerjoin.params.right">¶</a> – the right side of the join; this is any
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> object such as a <a class="reference internal" href="metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a> object, and
may also be a selectable-compatible object such as an ORM-mapped
class.</li>
<li><span class="target" id="sqlalchemy.sql.expression.Select.outerjoin.params.onclause"></span><strong>onclause</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Select.outerjoin.params.onclause">¶</a> – a SQL expression representing the ON clause of the
join. If left at <tt class="docutils literal"><span class="pre">None</span></tt>, <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a> will attempt to
join the two tables based on a foreign key relationship.</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p><a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a></p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a></p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.params">
<tt class="descname">params</tt><big>(</big><em>*optionaldict</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.params" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.params" title="sqlalchemy.sql.expression.ClauseElement.params"><tt class="xref py py-meth docutils literal"><span class="pre">params()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Return a copy with <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.bindparam" title="sqlalchemy.sql.expression.bindparam"><tt class="xref py py-func docutils literal"><span class="pre">bindparam()</span></tt></a> elements replaced.</p>
<p>Returns a copy of this ClauseElement with <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.bindparam" title="sqlalchemy.sql.expression.bindparam"><tt class="xref py py-func docutils literal"><span class="pre">bindparam()</span></tt></a>
elements replaced with values taken from the given dictionary:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="n">clause</span> <span class="o">=</span> <span class="n">column</span><span class="p">(</span><span class="s">'x'</span><span class="p">)</span> <span class="o">+</span> <span class="n">bindparam</span><span class="p">(</span><span class="s">'foo'</span><span class="p">)</span>
<span class="gp">>>> </span><span class="k">print</span> <span class="n">clause</span><span class="o">.</span><span class="n">compile</span><span class="p">()</span><span class="o">.</span><span class="n">params</span>
<span class="go">{'foo':None}</span>
<span class="gp">>>> </span><span class="k">print</span> <span class="n">clause</span><span class="o">.</span><span class="n">params</span><span class="p">({</span><span class="s">'foo'</span><span class="p">:</span><span class="mi">7</span><span class="p">})</span><span class="o">.</span><span class="n">compile</span><span class="p">()</span><span class="o">.</span><span class="n">params</span>
<span class="go">{'foo':7}</span></pre></div>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.prefix_with">
<tt class="descname">prefix_with</tt><big>(</big><em>*expr</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.prefix_with" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.HasPrefixes.prefix_with" title="sqlalchemy.sql.expression.HasPrefixes.prefix_with"><tt class="xref py py-meth docutils literal"><span class="pre">prefix_with()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.HasPrefixes" title="sqlalchemy.sql.expression.HasPrefixes"><tt class="xref py py-class docutils literal"><span class="pre">HasPrefixes</span></tt></a></div>
<p>Add one or more expressions following the statement keyword, i.e.
SELECT, INSERT, UPDATE, or DELETE. Generative.</p>
<p>This is used to support backend-specific prefix keywords such as those
provided by MySQL.</p>
<p>E.g.:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">stmt</span> <span class="o">=</span> <span class="n">table</span><span class="o">.</span><span class="n">insert</span><span class="p">()</span><span class="o">.</span><span class="n">prefix_with</span><span class="p">(</span><span class="s">"LOW_PRIORITY"</span><span class="p">,</span> <span class="n">dialect</span><span class="o">=</span><span class="s">"mysql"</span><span class="p">)</span></pre></div>
</div>
<p>Multiple prefixes can be specified by multiple calls
to <a class="reference internal" href="#sqlalchemy.sql.expression.Select.prefix_with" title="sqlalchemy.sql.expression.Select.prefix_with"><tt class="xref py py-meth docutils literal"><span class="pre">prefix_with()</span></tt></a>.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.Select.prefix_with.params.*expr"></span><strong>*expr</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Select.prefix_with.params.*expr">¶</a> – textual or <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a> construct which
will be rendered following the INSERT, UPDATE, or DELETE
keyword.</li>
<li><span class="target" id="sqlalchemy.sql.expression.Select.prefix_with.params.**kw"></span><strong>**kw</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Select.prefix_with.params.**kw">¶</a> – A single keyword ‘dialect’ is accepted. This is an
optional string dialect name which will
limit rendering of this prefix to only that dialect.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.Select.primary_key">
<tt class="descname">primary_key</tt><a class="headerlink" href="#sqlalchemy.sql.expression.Select.primary_key" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.primary_key" title="sqlalchemy.sql.expression.FromClause.primary_key"><tt class="xref py py-attr docutils literal"><span class="pre">primary_key</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return the collection of Column objects which comprise the
primary key of this FromClause.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.reduce_columns">
<tt class="descname">reduce_columns</tt><big>(</big><em>only_synonyms=True</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.reduce_columns" title="Permalink to this definition">¶</a></dt>
<dd><p>Return a new :func`.select` construct with redundantly
named, equivalently-valued columns removed from the columns clause.</p>
<p>“Redundant” here means two columns where one refers to the
other either based on foreign key, or via a simple equality
comparison in the WHERE clause of the statement. The primary purpose
of this method is to automatically construct a select statement
with all uniquely-named columns, without the need to use
table-qualified labels as <a class="reference internal" href="#sqlalchemy.sql.expression.Select.apply_labels" title="sqlalchemy.sql.expression.Select.apply_labels"><tt class="xref py py-meth docutils literal"><span class="pre">apply_labels()</span></tt></a> does.</p>
<p>When columns are omitted based on foreign key, the referred-to
column is the one that’s kept. When columns are omitted based on
WHERE eqivalence, the first column in the columns clause is the
one that’s kept.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><span class="target" id="sqlalchemy.sql.expression.Select.reduce_columns.params.only_synonyms"></span><strong>only_synonyms</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Select.reduce_columns.params.only_synonyms">¶</a> – when True, limit the removal of columns
to those which have the same name as the equivalent. Otherwise,
all columns that are equivalent to another are removed.</td>
</tr>
</tbody>
</table>
<div class="versionadded">
<p><span>New in version 0.8.</span></p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.replace_selectable">
<tt class="descname">replace_selectable</tt><big>(</big><em>old</em>, <em>alias</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.replace_selectable" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.replace_selectable" title="sqlalchemy.sql.expression.FromClause.replace_selectable"><tt class="xref py py-meth docutils literal"><span class="pre">replace_selectable()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>replace all occurrences of FromClause ‘old’ with the given Alias
object, returning a copy of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.scalar">
<tt class="descname">scalar</tt><big>(</big><em>*multiparams</em>, <em>**params</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.scalar" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.Executable.scalar" title="sqlalchemy.sql.expression.Executable.scalar"><tt class="xref py py-meth docutils literal"><span class="pre">scalar()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.Executable" title="sqlalchemy.sql.expression.Executable"><tt class="xref py py-class docutils literal"><span class="pre">Executable</span></tt></a></div>
<p>Compile and execute this <a class="reference internal" href="#sqlalchemy.sql.expression.Executable" title="sqlalchemy.sql.expression.Executable"><tt class="xref py py-class docutils literal"><span class="pre">Executable</span></tt></a>, returning the
result’s scalar representation.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.select">
<tt class="descname">select</tt><big>(</big><em>whereclause=None</em>, <em>**params</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.select" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.select" title="sqlalchemy.sql.expression.FromClause.select"><tt class="xref py py-meth docutils literal"><span class="pre">select()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>return a SELECT of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a> - general purpose
method which allows for arbitrary column lists.</p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.select_from">
<tt class="descname">select_from</tt><big>(</big><em>fromclause</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.select_from" title="Permalink to this definition">¶</a></dt>
<dd><p>return a new <a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a> construct with the
given FROM expression
merged into its list of FROM objects.</p>
<p>E.g.:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">table1</span> <span class="o">=</span> <span class="n">table</span><span class="p">(</span><span class="s">'t1'</span><span class="p">,</span> <span class="n">column</span><span class="p">(</span><span class="s">'a'</span><span class="p">))</span>
<span class="n">table2</span> <span class="o">=</span> <span class="n">table</span><span class="p">(</span><span class="s">'t2'</span><span class="p">,</span> <span class="n">column</span><span class="p">(</span><span class="s">'b'</span><span class="p">))</span>
<span class="n">s</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">table1</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">a</span><span class="p">])</span><span class="o">.</span>\
<span class="n">select_from</span><span class="p">(</span>
<span class="n">table1</span><span class="o">.</span><span class="n">join</span><span class="p">(</span><span class="n">table2</span><span class="p">,</span> <span class="n">table1</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">a</span><span class="o">==</span><span class="n">table2</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">b</span><span class="p">)</span>
<span class="p">)</span></pre></div>
</div>
<p>The “from” list is a unique set on the identity of each element,
so adding an already present <a class="reference internal" href="metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a> or other selectable
will have no effect. Passing a <a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> that refers
to an already present <a class="reference internal" href="metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a> or other selectable will have
the effect of concealing the presence of that selectable as
an individual element in the rendered FROM list, instead
rendering it into a JOIN clause.</p>
<p>While the typical purpose of <a class="reference internal" href="#sqlalchemy.sql.expression.Select.select_from" title="sqlalchemy.sql.expression.Select.select_from"><tt class="xref py py-meth docutils literal"><span class="pre">Select.select_from()</span></tt></a> is to
replace the default, derived FROM clause with a join, it can
also be called with individual table elements, multiple times
if desired, in the case that the FROM clause cannot be fully
derived from the columns clause:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">select</span><span class="p">([</span><span class="n">func</span><span class="o">.</span><span class="n">count</span><span class="p">(</span><span class="s">'*'</span><span class="p">)])</span><span class="o">.</span><span class="n">select_from</span><span class="p">(</span><span class="n">table1</span><span class="p">)</span></pre></div>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.self_group">
<tt class="descname">self_group</tt><big>(</big><em>against=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.self_group" title="Permalink to this definition">¶</a></dt>
<dd><p>return a ‘grouping’ construct as per the ClauseElement
specification.</p>
<p>This produces an element that can be embedded in an expression. Note
that this method is called automatically as needed when constructing
expressions and should not require explicit use.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.union">
<tt class="descname">union</tt><big>(</big><em>other</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.union" title="Permalink to this definition">¶</a></dt>
<dd><p>return a SQL UNION of this select() construct against the given
selectable.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.union_all">
<tt class="descname">union_all</tt><big>(</big><em>other</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.union_all" title="Permalink to this definition">¶</a></dt>
<dd><p>return a SQL UNION ALL of this select() construct against the given
selectable.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.unique_params">
<tt class="descname">unique_params</tt><big>(</big><em>*optionaldict</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.unique_params" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.unique_params" title="sqlalchemy.sql.expression.ClauseElement.unique_params"><tt class="xref py py-meth docutils literal"><span class="pre">unique_params()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Return a copy with <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.bindparam" title="sqlalchemy.sql.expression.bindparam"><tt class="xref py py-func docutils literal"><span class="pre">bindparam()</span></tt></a> elements replaced.</p>
<p>Same functionality as <tt class="docutils literal"><span class="pre">params()</span></tt>, except adds <cite>unique=True</cite>
to affected bind parameters so that multiple statements can be
used.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.where">
<tt class="descname">where</tt><big>(</big><em>whereclause</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.where" title="Permalink to this definition">¶</a></dt>
<dd><p>return a new select() construct with the given expression added to
its WHERE clause, joined to the existing clause via AND, if any.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.with_for_update">
<tt class="descname">with_for_update</tt><big>(</big><em>nowait=False</em>, <em>read=False</em>, <em>of=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.with_for_update" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect.with_for_update" title="sqlalchemy.sql.expression.GenerativeSelect.with_for_update"><tt class="xref py py-meth docutils literal"><span class="pre">with_for_update()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect" title="sqlalchemy.sql.expression.GenerativeSelect"><tt class="xref py py-class docutils literal"><span class="pre">GenerativeSelect</span></tt></a></div>
<p>Specify a <tt class="docutils literal"><span class="pre">FOR</span> <span class="pre">UPDATE</span></tt> clause for this <a class="reference internal" href="#sqlalchemy.sql.expression.GenerativeSelect" title="sqlalchemy.sql.expression.GenerativeSelect"><tt class="xref py py-class docutils literal"><span class="pre">GenerativeSelect</span></tt></a>.</p>
<p>E.g.:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">stmt</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">table</span><span class="p">])</span><span class="o">.</span><span class="n">with_for_update</span><span class="p">(</span><span class="n">nowait</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span></pre></div>
</div>
<p>On a database like Postgresql or Oracle, the above would render a
statement like:</p>
<div class="highlight-python"><pre>SELECT table.a, table.b FROM table FOR UPDATE NOWAIT</pre>
</div>
<p>on other backends, the <tt class="docutils literal"><span class="pre">nowait</span></tt> option is ignored and instead
would produce:</p>
<div class="highlight-python"><pre>SELECT table.a, table.b FROM table FOR UPDATE</pre>
</div>
<p>When called with no arguments, the statement will render with
the suffix <tt class="docutils literal"><span class="pre">FOR</span> <span class="pre">UPDATE</span></tt>. Additional arguments can then be
provided which allow for common database-specific
variants.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.Select.with_for_update.params.nowait"></span><strong>nowait</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Select.with_for_update.params.nowait">¶</a> – boolean; will render <tt class="docutils literal"><span class="pre">FOR</span> <span class="pre">UPDATE</span> <span class="pre">NOWAIT</span></tt> on Oracle
and Postgresql dialects.</li>
<li><span class="target" id="sqlalchemy.sql.expression.Select.with_for_update.params.read"></span><strong>read</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Select.with_for_update.params.read">¶</a> – boolean; will render <tt class="docutils literal"><span class="pre">LOCK</span> <span class="pre">IN</span> <span class="pre">SHARE</span> <span class="pre">MODE</span></tt> on MySQL,
<tt class="docutils literal"><span class="pre">FOR</span> <span class="pre">SHARE</span></tt> on Postgresql. On Postgresql, when combined with
<tt class="docutils literal"><span class="pre">nowait</span></tt>, will render <tt class="docutils literal"><span class="pre">FOR</span> <span class="pre">SHARE</span> <span class="pre">NOWAIT</span></tt>.</li>
<li><span class="target" id="sqlalchemy.sql.expression.Select.with_for_update.params.of"></span><strong>of</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.Select.with_for_update.params.of">¶</a> – SQL expression or list of SQL expression elements
(typically <a class="reference internal" href="metadata.html#sqlalchemy.schema.Column" title="sqlalchemy.schema.Column"><tt class="xref py py-class docutils literal"><span class="pre">Column</span></tt></a> objects or a compatible expression) which
will render into a <tt class="docutils literal"><span class="pre">FOR</span> <span class="pre">UPDATE</span> <span class="pre">OF</span></tt> clause; supported by PostgreSQL
and Oracle. May render as a table or as a column depending on
backend.</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="versionadded">
<p><span>New in version 0.9.0.</span></p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.with_hint">
<tt class="descname">with_hint</tt><big>(</big><em>selectable</em>, <em>text</em>, <em>dialect_name='*'</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.with_hint" title="Permalink to this definition">¶</a></dt>
<dd><p>Add an indexing hint for the given selectable to this
<a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a>.</p>
<p>The text of the hint is rendered in the appropriate
location for the database backend in use, relative
to the given <a class="reference internal" href="metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a> or <a class="reference internal" href="#sqlalchemy.sql.expression.Alias" title="sqlalchemy.sql.expression.Alias"><tt class="xref py py-class docutils literal"><span class="pre">Alias</span></tt></a> passed as the
<tt class="docutils literal"><span class="pre">selectable</span></tt> argument. The dialect implementation
typically uses Python string substitution syntax
with the token <tt class="docutils literal"><span class="pre">%(name)s</span></tt> to render the name of
the table or alias. E.g. when using Oracle, the
following:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">select</span><span class="p">([</span><span class="n">mytable</span><span class="p">])</span><span class="o">.</span>\
<span class="n">with_hint</span><span class="p">(</span><span class="n">mytable</span><span class="p">,</span> <span class="s">"index(</span><span class="si">%(name)s</span><span class="s"> ix_mytable)"</span><span class="p">)</span></pre></div>
</div>
<p>Would render SQL as:</p>
<div class="highlight-python"><pre>select /*+ index(mytable ix_mytable) */ ... from mytable</pre>
</div>
<p>The <tt class="docutils literal"><span class="pre">dialect_name</span></tt> option will limit the rendering of a particular
hint to a particular backend. Such as, to add hints for both Oracle
and Sybase simultaneously:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">select</span><span class="p">([</span><span class="n">mytable</span><span class="p">])</span><span class="o">.</span>\
<span class="n">with_hint</span><span class="p">(</span><span class="n">mytable</span><span class="p">,</span> <span class="s">"index(</span><span class="si">%(name)s</span><span class="s"> ix_mytable)"</span><span class="p">,</span> <span class="s">'oracle'</span><span class="p">)</span><span class="o">.</span>\
<span class="n">with_hint</span><span class="p">(</span><span class="n">mytable</span><span class="p">,</span> <span class="s">"WITH INDEX ix_mytable"</span><span class="p">,</span> <span class="s">'sybase'</span><span class="p">)</span></pre></div>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.Select.with_only_columns">
<tt class="descname">with_only_columns</tt><big>(</big><em>columns</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.Select.with_only_columns" title="Permalink to this definition">¶</a></dt>
<dd><p>Return a new <a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a> construct with its columns
clause replaced with the given columns.</p>
<div class="versionchanged">
<p><span>Changed in version 0.7.3: </span>Due to a bug fix, this method has a slight
behavioral change as of version 0.7.3.
Prior to version 0.7.3, the FROM clause of
a <a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a> was calculated upfront and as new columns
were added; in 0.7.3 and later it’s calculated
at compile time, fixing an issue regarding late binding
of columns to parent tables. This changes the behavior of
<a class="reference internal" href="#sqlalchemy.sql.expression.Select.with_only_columns" title="sqlalchemy.sql.expression.Select.with_only_columns"><tt class="xref py py-meth docutils literal"><span class="pre">Select.with_only_columns()</span></tt></a> in that FROM clauses no
longer represented in the new list are dropped,
but this behavior is more consistent in
that the FROM clauses are consistently derived from the
current columns clause. The original intent of this method
is to allow trimming of the existing columns list to be fewer
columns than originally present; the use case of replacing
the columns list with an entirely different one hadn’t
been anticipated until 0.7.3 was released; the usage
guidelines below illustrate how this should be done.</p>
</div>
<p>This method is exactly equivalent to as if the original
<a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a> had been called with the given columns
clause. I.e. a statement:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">s</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">table1</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">a</span><span class="p">,</span> <span class="n">table1</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">b</span><span class="p">])</span>
<span class="n">s</span> <span class="o">=</span> <span class="n">s</span><span class="o">.</span><span class="n">with_only_columns</span><span class="p">([</span><span class="n">table1</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">b</span><span class="p">])</span></pre></div>
</div>
<p>should be exactly equivalent to:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">s</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">table1</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">b</span><span class="p">])</span></pre></div>
</div>
<p>This means that FROM clauses which are only derived
from the column list will be discarded if the new column
list no longer contains that FROM:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="n">table1</span> <span class="o">=</span> <span class="n">table</span><span class="p">(</span><span class="s">'t1'</span><span class="p">,</span> <span class="n">column</span><span class="p">(</span><span class="s">'a'</span><span class="p">),</span> <span class="n">column</span><span class="p">(</span><span class="s">'b'</span><span class="p">))</span>
<span class="gp">>>> </span><span class="n">table2</span> <span class="o">=</span> <span class="n">table</span><span class="p">(</span><span class="s">'t2'</span><span class="p">,</span> <span class="n">column</span><span class="p">(</span><span class="s">'a'</span><span class="p">),</span> <span class="n">column</span><span class="p">(</span><span class="s">'b'</span><span class="p">))</span>
<span class="gp">>>> </span><span class="n">s1</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">table1</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">a</span><span class="p">,</span> <span class="n">table2</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">b</span><span class="p">])</span>
<span class="gp">>>> </span><span class="k">print</span> <span class="n">s1</span>
<span class="go">SELECT t1.a, t2.b FROM t1, t2</span>
<span class="gp">>>> </span><span class="n">s2</span> <span class="o">=</span> <span class="n">s1</span><span class="o">.</span><span class="n">with_only_columns</span><span class="p">([</span><span class="n">table2</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">b</span><span class="p">])</span>
<span class="gp">>>> </span><span class="k">print</span> <span class="n">s2</span>
<span class="go">SELECT t2.b FROM t1</span></pre></div>
</div>
<p>The preferred way to maintain a specific FROM clause
in the construct, assuming it won’t be represented anywhere
else (i.e. not in the WHERE clause, etc.) is to set it using
<a class="reference internal" href="#sqlalchemy.sql.expression.Select.select_from" title="sqlalchemy.sql.expression.Select.select_from"><tt class="xref py py-meth docutils literal"><span class="pre">Select.select_from()</span></tt></a>:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="n">s1</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">table1</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">a</span><span class="p">,</span> <span class="n">table2</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">b</span><span class="p">])</span><span class="o">.</span>\
<span class="gp">... </span> <span class="n">select_from</span><span class="p">(</span><span class="n">table1</span><span class="o">.</span><span class="n">join</span><span class="p">(</span><span class="n">table2</span><span class="p">,</span>
<span class="gp">... </span> <span class="n">table1</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">a</span><span class="o">==</span><span class="n">table2</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">a</span><span class="p">))</span>
<span class="gp">>>> </span><span class="n">s2</span> <span class="o">=</span> <span class="n">s1</span><span class="o">.</span><span class="n">with_only_columns</span><span class="p">([</span><span class="n">table2</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">b</span><span class="p">])</span>
<span class="gp">>>> </span><span class="k">print</span> <span class="n">s2</span>
<span class="go">SELECT t2.b FROM t1 JOIN t2 ON t1.a=t2.a</span></pre></div>
</div>
<p>Care should also be taken to use the correct
set of column objects passed to <a class="reference internal" href="#sqlalchemy.sql.expression.Select.with_only_columns" title="sqlalchemy.sql.expression.Select.with_only_columns"><tt class="xref py py-meth docutils literal"><span class="pre">Select.with_only_columns()</span></tt></a>.
Since the method is essentially equivalent to calling the
<a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a> construct in the first place with the given
columns, the columns passed to <a class="reference internal" href="#sqlalchemy.sql.expression.Select.with_only_columns" title="sqlalchemy.sql.expression.Select.with_only_columns"><tt class="xref py py-meth docutils literal"><span class="pre">Select.with_only_columns()</span></tt></a>
should usually be a subset of those which were passed
to the <a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a> construct, not those which are available
from the <tt class="docutils literal"><span class="pre">.c</span></tt> collection of that <a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a>. That
is:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">s</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">table1</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">a</span><span class="p">,</span> <span class="n">table1</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">b</span><span class="p">])</span><span class="o">.</span><span class="n">select_from</span><span class="p">(</span><span class="n">table1</span><span class="p">)</span>
<span class="n">s</span> <span class="o">=</span> <span class="n">s</span><span class="o">.</span><span class="n">with_only_columns</span><span class="p">([</span><span class="n">table1</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">b</span><span class="p">])</span></pre></div>
</div>
<p>and <strong>not</strong>:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="c"># usually incorrect</span>
<span class="n">s</span> <span class="o">=</span> <span class="n">s</span><span class="o">.</span><span class="n">with_only_columns</span><span class="p">([</span><span class="n">s</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">b</span><span class="p">])</span></pre></div>
</div>
<p>The latter would produce the SQL:</p>
<div class="highlight-python"><pre>SELECT b
FROM (SELECT t1.a AS a, t1.b AS b
FROM t1), t1</pre>
</div>
<p>Since the <a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a> construct is essentially being
asked to select both from <tt class="docutils literal"><span class="pre">table1</span></tt> as well as itself.</p>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.sql.expression.Selectable">
<em class="property">class </em><tt class="descclassname">sqlalchemy.sql.expression.</tt><tt class="descname">Selectable</tt><a class="headerlink" href="#sqlalchemy.sql.expression.Selectable" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.sql.expression.ClauseElement</span></tt></a></p>
<p>mark a class as being selectable</p>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.sql.expression.SelectBase">
<em class="property">class </em><tt class="descclassname">sqlalchemy.sql.expression.</tt><tt class="descname">SelectBase</tt><a class="headerlink" href="#sqlalchemy.sql.expression.SelectBase" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <a class="reference internal" href="#sqlalchemy.sql.expression.Executable" title="sqlalchemy.sql.expression.Executable"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.sql.expression.Executable</span></tt></a>, <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.sql.expression.FromClause</span></tt></a></p>
<p>Base class for SELECT statements.</p>
<p>This includes <a class="reference internal" href="#sqlalchemy.sql.expression.Select" title="sqlalchemy.sql.expression.Select"><tt class="xref py py-class docutils literal"><span class="pre">Select</span></tt></a>, <a class="reference internal" href="#sqlalchemy.sql.expression.CompoundSelect" title="sqlalchemy.sql.expression.CompoundSelect"><tt class="xref py py-class docutils literal"><span class="pre">CompoundSelect</span></tt></a> and
<a class="reference internal" href="#sqlalchemy.sql.expression.TextAsFrom" title="sqlalchemy.sql.expression.TextAsFrom"><tt class="xref py py-class docutils literal"><span class="pre">TextAsFrom</span></tt></a>.</p>
<dl class="method">
<dt id="sqlalchemy.sql.expression.SelectBase.as_scalar">
<tt class="descname">as_scalar</tt><big>(</big><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.SelectBase.as_scalar" title="Permalink to this definition">¶</a></dt>
<dd><p>return a ‘scalar’ representation of this selectable, which can be
used as a column expression.</p>
<p>Typically, a select statement which has only one column in its columns
clause is eligible to be used as a scalar expression.</p>
<p>The returned object is an instance of
<a class="reference internal" href="#sqlalchemy.sql.expression.ScalarSelect" title="sqlalchemy.sql.expression.ScalarSelect"><tt class="xref py py-class docutils literal"><span class="pre">ScalarSelect</span></tt></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.SelectBase.autocommit">
<tt class="descname">autocommit</tt><big>(</big><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.SelectBase.autocommit" title="Permalink to this definition">¶</a></dt>
<dd><p>return a new selectable with the ‘autocommit’ flag set to
True.</p>
<div class="deprecated">
<p><span>Deprecated since version 0.6: </span><tt class="docutils literal"><span class="pre">autocommit()</span></tt> is deprecated. Use <a class="reference internal" href="#sqlalchemy.sql.expression.Executable.execution_options" title="sqlalchemy.sql.expression.Executable.execution_options"><tt class="xref py py-meth docutils literal"><span class="pre">Executable.execution_options()</span></tt></a> with the ‘autocommit’ flag.</p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.SelectBase.cte">
<tt class="descname">cte</tt><big>(</big><em>name=None</em>, <em>recursive=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.SelectBase.cte" title="Permalink to this definition">¶</a></dt>
<dd><p>Return a new <a class="reference internal" href="#sqlalchemy.sql.expression.CTE" title="sqlalchemy.sql.expression.CTE"><tt class="xref py py-class docutils literal"><span class="pre">CTE</span></tt></a>, or Common Table Expression instance.</p>
<p>Common table expressions are a SQL standard whereby SELECT
statements can draw upon secondary statements specified along
with the primary statement, using a clause called “WITH”.
Special semantics regarding UNION can also be employed to
allow “recursive” queries, where a SELECT statement can draw
upon the set of rows that have previously been selected.</p>
<p>SQLAlchemy detects <a class="reference internal" href="#sqlalchemy.sql.expression.CTE" title="sqlalchemy.sql.expression.CTE"><tt class="xref py py-class docutils literal"><span class="pre">CTE</span></tt></a> objects, which are treated
similarly to <a class="reference internal" href="#sqlalchemy.sql.expression.Alias" title="sqlalchemy.sql.expression.Alias"><tt class="xref py py-class docutils literal"><span class="pre">Alias</span></tt></a> objects, as special elements
to be delivered to the FROM clause of the statement as well
as to a WITH clause at the top of the statement.</p>
<div class="versionadded">
<p><span>New in version 0.7.6.</span></p>
</div>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.SelectBase.cte.params.name"></span><strong>name</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.SelectBase.cte.params.name">¶</a> – name given to the common table expression. Like
<tt class="xref py py-meth docutils literal"><span class="pre">_FromClause.alias()</span></tt>, the name can be left as <tt class="docutils literal"><span class="pre">None</span></tt>
in which case an anonymous symbol will be used at query
compile time.</li>
<li><span class="target" id="sqlalchemy.sql.expression.SelectBase.cte.params.recursive"></span><strong>recursive</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.SelectBase.cte.params.recursive">¶</a> – if <tt class="docutils literal"><span class="pre">True</span></tt>, will render <tt class="docutils literal"><span class="pre">WITH</span> <span class="pre">RECURSIVE</span></tt>.
A recursive common table expression is intended to be used in
conjunction with UNION ALL in order to derive rows
from those already selected.</li>
</ul>
</td>
</tr>
</tbody>
</table>
<p>The following examples illustrate two examples from
Postgresql’s documentation at
<a class="reference external" href="http://www.postgresql.org/docs/8.4/static/queries-with.html">http://www.postgresql.org/docs/8.4/static/queries-with.html</a>.</p>
<p>Example 1, non recursive:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="p">(</span><span class="n">Table</span><span class="p">,</span> <span class="n">Column</span><span class="p">,</span> <span class="n">String</span><span class="p">,</span> <span class="n">Integer</span><span class="p">,</span>
<span class="n">MetaData</span><span class="p">,</span> <span class="n">select</span><span class="p">,</span> <span class="n">func</span><span class="p">)</span>
<span class="n">metadata</span> <span class="o">=</span> <span class="n">MetaData</span><span class="p">()</span>
<span class="n">orders</span> <span class="o">=</span> <span class="n">Table</span><span class="p">(</span><span class="s">'orders'</span><span class="p">,</span> <span class="n">metadata</span><span class="p">,</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'region'</span><span class="p">,</span> <span class="n">String</span><span class="p">),</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'amount'</span><span class="p">,</span> <span class="n">Integer</span><span class="p">),</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'product'</span><span class="p">,</span> <span class="n">String</span><span class="p">),</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'quantity'</span><span class="p">,</span> <span class="n">Integer</span><span class="p">)</span>
<span class="p">)</span>
<span class="n">regional_sales</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span>
<span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">region</span><span class="p">,</span>
<span class="n">func</span><span class="o">.</span><span class="n">sum</span><span class="p">(</span><span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">amount</span><span class="p">)</span><span class="o">.</span><span class="n">label</span><span class="p">(</span><span class="s">'total_sales'</span><span class="p">)</span>
<span class="p">])</span><span class="o">.</span><span class="n">group_by</span><span class="p">(</span><span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">region</span><span class="p">)</span><span class="o">.</span><span class="n">cte</span><span class="p">(</span><span class="s">"regional_sales"</span><span class="p">)</span>
<span class="n">top_regions</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">regional_sales</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">region</span><span class="p">])</span><span class="o">.</span>\
<span class="n">where</span><span class="p">(</span>
<span class="n">regional_sales</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">total_sales</span> <span class="o">></span>
<span class="n">select</span><span class="p">([</span>
<span class="n">func</span><span class="o">.</span><span class="n">sum</span><span class="p">(</span><span class="n">regional_sales</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">total_sales</span><span class="p">)</span><span class="o">/</span><span class="mi">10</span>
<span class="p">])</span>
<span class="p">)</span><span class="o">.</span><span class="n">cte</span><span class="p">(</span><span class="s">"top_regions"</span><span class="p">)</span>
<span class="n">statement</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span>
<span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">region</span><span class="p">,</span>
<span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">product</span><span class="p">,</span>
<span class="n">func</span><span class="o">.</span><span class="n">sum</span><span class="p">(</span><span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">quantity</span><span class="p">)</span><span class="o">.</span><span class="n">label</span><span class="p">(</span><span class="s">"product_units"</span><span class="p">),</span>
<span class="n">func</span><span class="o">.</span><span class="n">sum</span><span class="p">(</span><span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">amount</span><span class="p">)</span><span class="o">.</span><span class="n">label</span><span class="p">(</span><span class="s">"product_sales"</span><span class="p">)</span>
<span class="p">])</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">region</span><span class="o">.</span><span class="n">in_</span><span class="p">(</span>
<span class="n">select</span><span class="p">([</span><span class="n">top_regions</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">region</span><span class="p">])</span>
<span class="p">))</span><span class="o">.</span><span class="n">group_by</span><span class="p">(</span><span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">region</span><span class="p">,</span> <span class="n">orders</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">product</span><span class="p">)</span>
<span class="n">result</span> <span class="o">=</span> <span class="n">conn</span><span class="o">.</span><span class="n">execute</span><span class="p">(</span><span class="n">statement</span><span class="p">)</span><span class="o">.</span><span class="n">fetchall</span><span class="p">()</span></pre></div>
</div>
<p>Example 2, WITH RECURSIVE:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="p">(</span><span class="n">Table</span><span class="p">,</span> <span class="n">Column</span><span class="p">,</span> <span class="n">String</span><span class="p">,</span> <span class="n">Integer</span><span class="p">,</span>
<span class="n">MetaData</span><span class="p">,</span> <span class="n">select</span><span class="p">,</span> <span class="n">func</span><span class="p">)</span>
<span class="n">metadata</span> <span class="o">=</span> <span class="n">MetaData</span><span class="p">()</span>
<span class="n">parts</span> <span class="o">=</span> <span class="n">Table</span><span class="p">(</span><span class="s">'parts'</span><span class="p">,</span> <span class="n">metadata</span><span class="p">,</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'part'</span><span class="p">,</span> <span class="n">String</span><span class="p">),</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'sub_part'</span><span class="p">,</span> <span class="n">String</span><span class="p">),</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'quantity'</span><span class="p">,</span> <span class="n">Integer</span><span class="p">),</span>
<span class="p">)</span>
<span class="n">included_parts</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span>
<span class="n">parts</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">sub_part</span><span class="p">,</span>
<span class="n">parts</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">part</span><span class="p">,</span>
<span class="n">parts</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">quantity</span><span class="p">])</span><span class="o">.</span>\
<span class="n">where</span><span class="p">(</span><span class="n">parts</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">part</span><span class="o">==</span><span class="s">'our part'</span><span class="p">)</span><span class="o">.</span>\
<span class="n">cte</span><span class="p">(</span><span class="n">recursive</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span>
<span class="n">incl_alias</span> <span class="o">=</span> <span class="n">included_parts</span><span class="o">.</span><span class="n">alias</span><span class="p">()</span>
<span class="n">parts_alias</span> <span class="o">=</span> <span class="n">parts</span><span class="o">.</span><span class="n">alias</span><span class="p">()</span>
<span class="n">included_parts</span> <span class="o">=</span> <span class="n">included_parts</span><span class="o">.</span><span class="n">union_all</span><span class="p">(</span>
<span class="n">select</span><span class="p">([</span>
<span class="n">parts_alias</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">sub_part</span><span class="p">,</span>
<span class="n">parts_alias</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">part</span><span class="p">,</span>
<span class="n">parts_alias</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">quantity</span>
<span class="p">])</span><span class="o">.</span>
<span class="n">where</span><span class="p">(</span><span class="n">parts_alias</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">part</span><span class="o">==</span><span class="n">incl_alias</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">sub_part</span><span class="p">)</span>
<span class="p">)</span>
<span class="n">statement</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span>
<span class="n">included_parts</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">sub_part</span><span class="p">,</span>
<span class="n">func</span><span class="o">.</span><span class="n">sum</span><span class="p">(</span><span class="n">included_parts</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">quantity</span><span class="p">)</span><span class="o">.</span>
<span class="n">label</span><span class="p">(</span><span class="s">'total_quantity'</span><span class="p">)</span>
<span class="p">])</span><span class="o">.</span>\
<span class="n">group_by</span><span class="p">(</span><span class="n">included_parts</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">sub_part</span><span class="p">)</span>
<span class="n">result</span> <span class="o">=</span> <span class="n">conn</span><span class="o">.</span><span class="n">execute</span><span class="p">(</span><span class="n">statement</span><span class="p">)</span><span class="o">.</span><span class="n">fetchall</span><span class="p">()</span></pre></div>
</div>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="../orm/query.html#sqlalchemy.orm.query.Query.cte" title="sqlalchemy.orm.query.Query.cte"><tt class="xref py py-meth docutils literal"><span class="pre">orm.query.Query.cte()</span></tt></a> - ORM version of
<a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase.cte" title="sqlalchemy.sql.expression.SelectBase.cte"><tt class="xref py py-meth docutils literal"><span class="pre">SelectBase.cte()</span></tt></a>.</p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.SelectBase.label">
<tt class="descname">label</tt><big>(</big><em>name</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.SelectBase.label" title="Permalink to this definition">¶</a></dt>
<dd><p>return a ‘scalar’ representation of this selectable, embedded as a
subquery with a label.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase.as_scalar" title="sqlalchemy.sql.expression.SelectBase.as_scalar"><tt class="xref py py-meth docutils literal"><span class="pre">as_scalar()</span></tt></a>.</p>
</div>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.sql.expression.TableClause">
<em class="property">class </em><tt class="descclassname">sqlalchemy.sql.expression.</tt><tt class="descname">TableClause</tt><big>(</big><em>name</em>, <em>*columns</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.TableClause" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.sql.expression.Immutable</span></tt>, <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.sql.expression.FromClause</span></tt></a></p>
<p>Represents a minimal “table” construct.</p>
<p>This is a lightweight table object that has only a name and a
collection of columns, which are typically produced
by the <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.column" title="sqlalchemy.sql.expression.column"><tt class="xref py py-func docutils literal"><span class="pre">expression.column()</span></tt></a> function:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy.sql</span> <span class="kn">import</span> <span class="n">table</span><span class="p">,</span> <span class="n">column</span>
<span class="n">user</span> <span class="o">=</span> <span class="n">table</span><span class="p">(</span><span class="s">"user"</span><span class="p">,</span>
<span class="n">column</span><span class="p">(</span><span class="s">"id"</span><span class="p">),</span>
<span class="n">column</span><span class="p">(</span><span class="s">"name"</span><span class="p">),</span>
<span class="n">column</span><span class="p">(</span><span class="s">"description"</span><span class="p">),</span>
<span class="p">)</span></pre></div>
</div>
<p>The <a class="reference internal" href="#sqlalchemy.sql.expression.TableClause" title="sqlalchemy.sql.expression.TableClause"><tt class="xref py py-class docutils literal"><span class="pre">TableClause</span></tt></a> construct serves as the base for
the more commonly used <a class="reference internal" href="metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a> object, providing
the usual set of <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> services including
the <tt class="docutils literal"><span class="pre">.c.</span></tt> collection and statement generation methods.</p>
<p>It does <strong>not</strong> provide all the additional schema-level services
of <a class="reference internal" href="metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a>, including constraints, references to other
tables, or support for <a class="reference internal" href="metadata.html#sqlalchemy.schema.MetaData" title="sqlalchemy.schema.MetaData"><tt class="xref py py-class docutils literal"><span class="pre">MetaData</span></tt></a>-level services. It’s useful
on its own as an ad-hoc construct used to generate quick SQL
statements when a more fully fledged <a class="reference internal" href="metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a>
is not on hand.</p>
<dl class="method">
<dt id="sqlalchemy.sql.expression.TableClause.__init__">
<tt class="descname">__init__</tt><big>(</big><em>name</em>, <em>*columns</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.TableClause.__init__" title="Permalink to this definition">¶</a></dt>
<dd><p>Construct a new <a class="reference internal" href="#sqlalchemy.sql.expression.TableClause" title="sqlalchemy.sql.expression.TableClause"><tt class="xref py py-class docutils literal"><span class="pre">TableClause</span></tt></a> object.</p>
<p>This constructor is mirrored as a public API function; see <a class="reference internal" href="#sqlalchemy.sql.expression.table" title="sqlalchemy.sql.expression.table"><tt class="xref py py-func docutils literal"><span class="pre">table()</span></tt></a> for a full usage and argument description.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.TableClause.alias">
<tt class="descname">alias</tt><big>(</big><em>name=None</em>, <em>flat=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.TableClause.alias" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.alias" title="sqlalchemy.sql.expression.FromClause.alias"><tt class="xref py py-meth docutils literal"><span class="pre">alias()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>return an alias of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<p>This is shorthand for calling:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="n">alias</span>
<span class="n">a</span> <span class="o">=</span> <span class="n">alias</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">name</span><span class="o">=</span><span class="n">name</span><span class="p">)</span></pre></div>
</div>
<p>See <a class="reference internal" href="#sqlalchemy.sql.expression.alias" title="sqlalchemy.sql.expression.alias"><tt class="xref py py-func docutils literal"><span class="pre">alias()</span></tt></a> for details.</p>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.TableClause.c">
<tt class="descname">c</tt><a class="headerlink" href="#sqlalchemy.sql.expression.TableClause.c" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.c" title="sqlalchemy.sql.expression.FromClause.c"><tt class="xref py py-attr docutils literal"><span class="pre">c</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>An alias for the <a class="reference internal" href="#sqlalchemy.sql.expression.TableClause.columns" title="sqlalchemy.sql.expression.TableClause.columns"><tt class="xref py py-attr docutils literal"><span class="pre">columns</span></tt></a> attribute.</p>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.TableClause.columns">
<tt class="descname">columns</tt><a class="headerlink" href="#sqlalchemy.sql.expression.TableClause.columns" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.columns" title="sqlalchemy.sql.expression.FromClause.columns"><tt class="xref py py-attr docutils literal"><span class="pre">columns</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>A named-based collection of <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> objects
maintained by this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<p>The <a class="reference internal" href="#sqlalchemy.sql.expression.TableClause.columns" title="sqlalchemy.sql.expression.TableClause.columns"><tt class="xref py py-attr docutils literal"><span class="pre">columns</span></tt></a>, or <a class="reference internal" href="#sqlalchemy.sql.expression.TableClause.c" title="sqlalchemy.sql.expression.TableClause.c"><tt class="xref py py-attr docutils literal"><span class="pre">c</span></tt></a> collection, is the gateway
to the construction of SQL expressions using table-bound or
other selectable-bound columns:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">select</span><span class="p">([</span><span class="n">mytable</span><span class="p">])</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="n">mytable</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">somecolumn</span> <span class="o">==</span> <span class="mi">5</span><span class="p">)</span></pre></div>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.TableClause.compare">
<tt class="descname">compare</tt><big>(</big><em>other</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.TableClause.compare" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.compare" title="sqlalchemy.sql.expression.ClauseElement.compare"><tt class="xref py py-meth docutils literal"><span class="pre">compare()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Compare this ClauseElement to the given ClauseElement.</p>
<p>Subclasses should override the default behavior, which is a
straight identity comparison.</p>
<p>**kw are arguments consumed by subclass compare() methods and
may be used to modify the criteria for comparison.
(see <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a>)</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.TableClause.compile">
<tt class="descname">compile</tt><big>(</big><em>bind=None</em>, <em>dialect=None</em>, <em>**kw</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.TableClause.compile" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.compile" title="sqlalchemy.sql.expression.ClauseElement.compile"><tt class="xref py py-meth docutils literal"><span class="pre">compile()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Compile this SQL expression.</p>
<p>The return value is a <a class="reference internal" href="internals.html#sqlalchemy.engine.interfaces.Compiled" title="sqlalchemy.engine.interfaces.Compiled"><tt class="xref py py-class docutils literal"><span class="pre">Compiled</span></tt></a> object.
Calling <tt class="docutils literal"><span class="pre">str()</span></tt> or <tt class="docutils literal"><span class="pre">unicode()</span></tt> on the returned value will yield a
string representation of the result. The
<a class="reference internal" href="internals.html#sqlalchemy.engine.interfaces.Compiled" title="sqlalchemy.engine.interfaces.Compiled"><tt class="xref py py-class docutils literal"><span class="pre">Compiled</span></tt></a> object also can return a
dictionary of bind parameter names and values
using the <tt class="docutils literal"><span class="pre">params</span></tt> accessor.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.TableClause.compile.params.bind"></span><strong>bind</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.TableClause.compile.params.bind">¶</a> – An <tt class="docutils literal"><span class="pre">Engine</span></tt> or <tt class="docutils literal"><span class="pre">Connection</span></tt> from which a
<tt class="docutils literal"><span class="pre">Compiled</span></tt> will be acquired. This argument takes precedence over
this <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a>‘s bound engine, if any.</li>
<li><span class="target" id="sqlalchemy.sql.expression.TableClause.compile.params.column_keys"></span><strong>column_keys</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.TableClause.compile.params.column_keys">¶</a> – Used for INSERT and UPDATE statements, a list of
column names which should be present in the VALUES clause of the
compiled statement. If <tt class="docutils literal"><span class="pre">None</span></tt>, all columns from the target table
object are rendered.</li>
<li><span class="target" id="sqlalchemy.sql.expression.TableClause.compile.params.dialect"></span><strong>dialect</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.TableClause.compile.params.dialect">¶</a> – A <tt class="docutils literal"><span class="pre">Dialect</span></tt> instance from which a <tt class="docutils literal"><span class="pre">Compiled</span></tt>
will be acquired. This argument takes precedence over the <cite>bind</cite>
argument as well as this <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a>‘s bound engine,
if any.</li>
<li><span class="target" id="sqlalchemy.sql.expression.TableClause.compile.params.inline"></span><strong>inline</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.TableClause.compile.params.inline">¶</a> – Used for INSERT statements, for a dialect which does
not support inline retrieval of newly generated primary key
columns, will force the expression used to create the new primary
key value to be rendered inline within the INSERT statement’s
VALUES clause. This typically refers to Sequence execution but may
also refer to any server-side default generation function
associated with a primary key <cite>Column</cite>.</li>
<li><span class="target" id="sqlalchemy.sql.expression.TableClause.compile.params.compile_kwargs"></span><strong>compile_kwargs</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.TableClause.compile.params.compile_kwargs">¶</a> – <p>optional dictionary of additional parameters
that will be passed through to the compiler within all “visit”
methods. This allows any custom flag to be passed through to
a custom compilation construct, for example. It is also used
for the case of passing the <tt class="docutils literal"><span class="pre">literal_binds</span></tt> flag through:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy.sql</span> <span class="kn">import</span> <span class="n">table</span><span class="p">,</span> <span class="n">column</span><span class="p">,</span> <span class="n">select</span>
<span class="n">t</span> <span class="o">=</span> <span class="n">table</span><span class="p">(</span><span class="s">'t'</span><span class="p">,</span> <span class="n">column</span><span class="p">(</span><span class="s">'x'</span><span class="p">))</span>
<span class="n">s</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">t</span><span class="p">])</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="n">t</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">x</span> <span class="o">==</span> <span class="mi">5</span><span class="p">)</span>
<span class="k">print</span> <span class="n">s</span><span class="o">.</span><span class="n">compile</span><span class="p">(</span><span class="n">compile_kwargs</span><span class="o">=</span><span class="p">{</span><span class="s">"literal_binds"</span><span class="p">:</span> <span class="bp">True</span><span class="p">})</span></pre></div>
</div>
<div class="versionadded">
<p><span>New in version 0.9.0.</span></p>
</div>
</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="../faq.html#faq-sql-expression-string"><em>How do I render SQL expressions as strings, possibly with bound parameters inlined?</em></a></p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.TableClause.correspond_on_equivalents">
<tt class="descname">correspond_on_equivalents</tt><big>(</big><em>column</em>, <em>equivalents</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.TableClause.correspond_on_equivalents" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.correspond_on_equivalents" title="sqlalchemy.sql.expression.FromClause.correspond_on_equivalents"><tt class="xref py py-meth docutils literal"><span class="pre">correspond_on_equivalents()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return corresponding_column for the given column, or if None
search for a match in the given dictionary.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.TableClause.corresponding_column">
<tt class="descname">corresponding_column</tt><big>(</big><em>column</em>, <em>require_embedded=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.TableClause.corresponding_column" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.corresponding_column" title="sqlalchemy.sql.expression.FromClause.corresponding_column"><tt class="xref py py-meth docutils literal"><span class="pre">corresponding_column()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Given a <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a>, return the exported
<a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> object from this <a class="reference internal" href="#sqlalchemy.sql.expression.Selectable" title="sqlalchemy.sql.expression.Selectable"><tt class="xref py py-class docutils literal"><span class="pre">Selectable</span></tt></a>
which corresponds to that original
<a class="reference internal" href="metadata.html#sqlalchemy.schema.Column" title="sqlalchemy.schema.Column"><tt class="xref py py-class docutils literal"><span class="pre">Column</span></tt></a> via a common ancestor
column.</p>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.TableClause.corresponding_column.params.column"></span><strong>column</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.TableClause.corresponding_column.params.column">¶</a> – the target <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> to be matched</li>
<li><span class="target" id="sqlalchemy.sql.expression.TableClause.corresponding_column.params.require_embedded"></span><strong>require_embedded</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.TableClause.corresponding_column.params.require_embedded">¶</a> – only return corresponding columns for
the given <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a>, if the given
<a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ColumnElement" title="sqlalchemy.sql.expression.ColumnElement"><tt class="xref py py-class docutils literal"><span class="pre">ColumnElement</span></tt></a> is actually present within a sub-element
of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>. Normally the column will match if
it merely shares a common ancestor with one of the exported
columns of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</li>
</ul>
</td>
</tr>
</tbody>
</table>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.TableClause.count">
<tt class="descname">count</tt><big>(</big><em>whereclause=None</em>, <em>**params</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.TableClause.count" title="Permalink to this definition">¶</a></dt>
<dd><p>return a SELECT COUNT generated against this
<a class="reference internal" href="#sqlalchemy.sql.expression.TableClause" title="sqlalchemy.sql.expression.TableClause"><tt class="xref py py-class docutils literal"><span class="pre">TableClause</span></tt></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.TableClause.delete">
<tt class="descname">delete</tt><big>(</big><em>whereclause=None</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.TableClause.delete" title="Permalink to this definition">¶</a></dt>
<dd><p>Generate a <a class="reference internal" href="dml.html#sqlalchemy.sql.expression.delete" title="sqlalchemy.sql.expression.delete"><tt class="xref py py-func docutils literal"><span class="pre">delete()</span></tt></a> construct against this
<a class="reference internal" href="#sqlalchemy.sql.expression.TableClause" title="sqlalchemy.sql.expression.TableClause"><tt class="xref py py-class docutils literal"><span class="pre">TableClause</span></tt></a>.</p>
<p>E.g.:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">table</span><span class="o">.</span><span class="n">delete</span><span class="p">()</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="n">table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span><span class="o">==</span><span class="mi">7</span><span class="p">)</span></pre></div>
</div>
<p>See <a class="reference internal" href="dml.html#sqlalchemy.sql.expression.delete" title="sqlalchemy.sql.expression.delete"><tt class="xref py py-func docutils literal"><span class="pre">delete()</span></tt></a> for argument and usage information.</p>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.TableClause.foreign_keys">
<tt class="descname">foreign_keys</tt><a class="headerlink" href="#sqlalchemy.sql.expression.TableClause.foreign_keys" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.foreign_keys" title="sqlalchemy.sql.expression.FromClause.foreign_keys"><tt class="xref py py-attr docutils literal"><span class="pre">foreign_keys</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return the collection of ForeignKey objects which this
FromClause references.</p>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.TableClause.implicit_returning">
<tt class="descname">implicit_returning</tt><em class="property"> = False</em><a class="headerlink" href="#sqlalchemy.sql.expression.TableClause.implicit_returning" title="Permalink to this definition">¶</a></dt>
<dd><p><a class="reference internal" href="#sqlalchemy.sql.expression.TableClause" title="sqlalchemy.sql.expression.TableClause"><tt class="xref py py-class docutils literal"><span class="pre">TableClause</span></tt></a> doesn’t support having a primary key or column
-level defaults, so implicit returning doesn’t apply.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.TableClause.insert">
<tt class="descname">insert</tt><big>(</big><em>values=None</em>, <em>inline=False</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.TableClause.insert" title="Permalink to this definition">¶</a></dt>
<dd><p>Generate an <a class="reference internal" href="dml.html#sqlalchemy.sql.expression.insert" title="sqlalchemy.sql.expression.insert"><tt class="xref py py-func docutils literal"><span class="pre">insert()</span></tt></a> construct against this
<a class="reference internal" href="#sqlalchemy.sql.expression.TableClause" title="sqlalchemy.sql.expression.TableClause"><tt class="xref py py-class docutils literal"><span class="pre">TableClause</span></tt></a>.</p>
<p>E.g.:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">table</span><span class="o">.</span><span class="n">insert</span><span class="p">()</span><span class="o">.</span><span class="n">values</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s">'foo'</span><span class="p">)</span></pre></div>
</div>
<p>See <a class="reference internal" href="dml.html#sqlalchemy.sql.expression.insert" title="sqlalchemy.sql.expression.insert"><tt class="xref py py-func docutils literal"><span class="pre">insert()</span></tt></a> for argument and usage information.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.TableClause.is_derived_from">
<tt class="descname">is_derived_from</tt><big>(</big><em>fromclause</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.TableClause.is_derived_from" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.is_derived_from" title="sqlalchemy.sql.expression.FromClause.is_derived_from"><tt class="xref py py-meth docutils literal"><span class="pre">is_derived_from()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return True if this FromClause is ‘derived’ from the given
FromClause.</p>
<p>An example would be an Alias of a Table is derived from that Table.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.TableClause.join">
<tt class="descname">join</tt><big>(</big><em>right</em>, <em>onclause=None</em>, <em>isouter=False</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.TableClause.join" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">join()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return a <a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> from this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>
to another <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<p>E.g.:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="n">join</span>
<span class="n">j</span> <span class="o">=</span> <span class="n">user_table</span><span class="o">.</span><span class="n">join</span><span class="p">(</span><span class="n">address_table</span><span class="p">,</span>
<span class="n">user_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span> <span class="o">==</span> <span class="n">address_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">user_id</span><span class="p">)</span>
<span class="n">stmt</span> <span class="o">=</span> <span class="n">select</span><span class="p">([</span><span class="n">user_table</span><span class="p">])</span><span class="o">.</span><span class="n">select_from</span><span class="p">(</span><span class="n">j</span><span class="p">)</span></pre></div>
</div>
<p>would emit SQL along the lines of:</p>
<div class="highlight-python"><pre>SELECT user.id, user.name FROM user
JOIN address ON user.id = address.user_id</pre>
</div>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.TableClause.join.params.right"></span><strong>right</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.TableClause.join.params.right">¶</a> – the right side of the join; this is any
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> object such as a <a class="reference internal" href="metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a> object, and
may also be a selectable-compatible object such as an ORM-mapped
class.</li>
<li><span class="target" id="sqlalchemy.sql.expression.TableClause.join.params.onclause"></span><strong>onclause</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.TableClause.join.params.onclause">¶</a> – a SQL expression representing the ON clause of the
join. If left at <tt class="docutils literal"><span class="pre">None</span></tt>, <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a> will attempt to
join the two tables based on a foreign key relationship.</li>
<li><span class="target" id="sqlalchemy.sql.expression.TableClause.join.params.isouter"></span><strong>isouter</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.TableClause.join.params.isouter">¶</a> – if True, render a LEFT OUTER JOIN, instead of JOIN.</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p><a class="reference internal" href="#sqlalchemy.sql.expression.join" title="sqlalchemy.sql.expression.join"><tt class="xref py py-func docutils literal"><span class="pre">join()</span></tt></a> - standalone function</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> - the type of object produced</p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.TableClause.outerjoin">
<tt class="descname">outerjoin</tt><big>(</big><em>right</em>, <em>onclause=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.TableClause.outerjoin" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.outerjoin" title="sqlalchemy.sql.expression.FromClause.outerjoin"><tt class="xref py py-meth docutils literal"><span class="pre">outerjoin()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return a <a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a> from this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>
to another <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>, with the “isouter” flag set to
True.</p>
<p>E.g.:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="n">outerjoin</span>
<span class="n">j</span> <span class="o">=</span> <span class="n">user_table</span><span class="o">.</span><span class="n">outerjoin</span><span class="p">(</span><span class="n">address_table</span><span class="p">,</span>
<span class="n">user_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span> <span class="o">==</span> <span class="n">address_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">user_id</span><span class="p">)</span></pre></div>
</div>
<p>The above is equivalent to:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">j</span> <span class="o">=</span> <span class="n">user_table</span><span class="o">.</span><span class="n">join</span><span class="p">(</span>
<span class="n">address_table</span><span class="p">,</span>
<span class="n">user_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span> <span class="o">==</span> <span class="n">address_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">user_id</span><span class="p">,</span>
<span class="n">isouter</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span></pre></div>
</div>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first last simple">
<li><span class="target" id="sqlalchemy.sql.expression.TableClause.outerjoin.params.right"></span><strong>right</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.TableClause.outerjoin.params.right">¶</a> – the right side of the join; this is any
<a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a> object such as a <a class="reference internal" href="metadata.html#sqlalchemy.schema.Table" title="sqlalchemy.schema.Table"><tt class="xref py py-class docutils literal"><span class="pre">Table</span></tt></a> object, and
may also be a selectable-compatible object such as an ORM-mapped
class.</li>
<li><span class="target" id="sqlalchemy.sql.expression.TableClause.outerjoin.params.onclause"></span><strong>onclause</strong><a class="paramlink headerlink reference internal" href="#sqlalchemy.sql.expression.TableClause.outerjoin.params.onclause">¶</a> – a SQL expression representing the ON clause of the
join. If left at <tt class="docutils literal"><span class="pre">None</span></tt>, <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a> will attempt to
join the two tables based on a foreign key relationship.</li>
</ul>
</td>
</tr>
</tbody>
</table>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p><a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.join" title="sqlalchemy.sql.expression.FromClause.join"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.join()</span></tt></a></p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.Join" title="sqlalchemy.sql.expression.Join"><tt class="xref py py-class docutils literal"><span class="pre">Join</span></tt></a></p>
</div>
</dd></dl>
<dl class="attribute">
<dt id="sqlalchemy.sql.expression.TableClause.primary_key">
<tt class="descname">primary_key</tt><a class="headerlink" href="#sqlalchemy.sql.expression.TableClause.primary_key" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.primary_key" title="sqlalchemy.sql.expression.FromClause.primary_key"><tt class="xref py py-attr docutils literal"><span class="pre">primary_key</span></tt></a> <em>attribute of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>Return the collection of Column objects which comprise the
primary key of this FromClause.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.TableClause.replace_selectable">
<tt class="descname">replace_selectable</tt><big>(</big><em>old</em>, <em>alias</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.TableClause.replace_selectable" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.replace_selectable" title="sqlalchemy.sql.expression.FromClause.replace_selectable"><tt class="xref py py-meth docutils literal"><span class="pre">replace_selectable()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>replace all occurrences of FromClause ‘old’ with the given Alias
object, returning a copy of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.TableClause.select">
<tt class="descname">select</tt><big>(</big><em>whereclause=None</em>, <em>**params</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.TableClause.select" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.select" title="sqlalchemy.sql.expression.FromClause.select"><tt class="xref py py-meth docutils literal"><span class="pre">select()</span></tt></a> <em>method of</em> <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a></div>
<p>return a SELECT of this <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause" title="sqlalchemy.sql.expression.FromClause"><tt class="xref py py-class docutils literal"><span class="pre">FromClause</span></tt></a>.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a> - general purpose
method which allows for arbitrary column lists.</p>
</div>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.TableClause.self_group">
<tt class="descname">self_group</tt><big>(</big><em>against=None</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.TableClause.self_group" title="Permalink to this definition">¶</a></dt>
<dd><div class="inherited-member container">
<em>inherited from the</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement.self_group" title="sqlalchemy.sql.expression.ClauseElement.self_group"><tt class="xref py py-meth docutils literal"><span class="pre">self_group()</span></tt></a> <em>method of</em> <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a></div>
<p>Apply a ‘grouping’ to this <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a>.</p>
<p>This method is overridden by subclasses to return a
“grouping” construct, i.e. parenthesis. In particular
it’s used by “binary” expressions to provide a grouping
around themselves when placed into a larger expression,
as well as by <a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a> constructs when placed into
the FROM clause of another <a class="reference internal" href="#sqlalchemy.sql.expression.select" title="sqlalchemy.sql.expression.select"><tt class="xref py py-func docutils literal"><span class="pre">select()</span></tt></a>. (Note that
subqueries should be normally created using the
<a class="reference internal" href="#sqlalchemy.sql.expression.Select.alias" title="sqlalchemy.sql.expression.Select.alias"><tt class="xref py py-meth docutils literal"><span class="pre">Select.alias()</span></tt></a> method, as many platforms require
nested SELECT statements to be named).</p>
<p>As expressions are composed together, the application of
<a class="reference internal" href="#sqlalchemy.sql.expression.TableClause.self_group" title="sqlalchemy.sql.expression.TableClause.self_group"><tt class="xref py py-meth docutils literal"><span class="pre">self_group()</span></tt></a> is automatic - end-user code should never
need to use this method directly. Note that SQLAlchemy’s
clause constructs take operator precedence into account -
so parenthesis might not be needed, for example, in
an expression like <tt class="docutils literal"><span class="pre">x</span> <span class="pre">OR</span> <span class="pre">(y</span> <span class="pre">AND</span> <span class="pre">z)</span></tt> - AND takes precedence
over OR.</p>
<p>The base <a class="reference internal" href="#sqlalchemy.sql.expression.TableClause.self_group" title="sqlalchemy.sql.expression.TableClause.self_group"><tt class="xref py py-meth docutils literal"><span class="pre">self_group()</span></tt></a> method of <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.ClauseElement" title="sqlalchemy.sql.expression.ClauseElement"><tt class="xref py py-class docutils literal"><span class="pre">ClauseElement</span></tt></a>
just returns self.</p>
</dd></dl>
<dl class="method">
<dt id="sqlalchemy.sql.expression.TableClause.update">
<tt class="descname">update</tt><big>(</big><em>whereclause=None</em>, <em>values=None</em>, <em>inline=False</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.TableClause.update" title="Permalink to this definition">¶</a></dt>
<dd><p>Generate an <a class="reference internal" href="dml.html#sqlalchemy.sql.expression.update" title="sqlalchemy.sql.expression.update"><tt class="xref py py-func docutils literal"><span class="pre">update()</span></tt></a> construct against this
<a class="reference internal" href="#sqlalchemy.sql.expression.TableClause" title="sqlalchemy.sql.expression.TableClause"><tt class="xref py py-class docutils literal"><span class="pre">TableClause</span></tt></a>.</p>
<p>E.g.:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">table</span><span class="o">.</span><span class="n">update</span><span class="p">()</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="n">table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">id</span><span class="o">==</span><span class="mi">7</span><span class="p">)</span><span class="o">.</span><span class="n">values</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s">'foo'</span><span class="p">)</span></pre></div>
</div>
<p>See <a class="reference internal" href="dml.html#sqlalchemy.sql.expression.update" title="sqlalchemy.sql.expression.update"><tt class="xref py py-func docutils literal"><span class="pre">update()</span></tt></a> for argument and usage information.</p>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.sql.expression.TextAsFrom">
<em class="property">class </em><tt class="descclassname">sqlalchemy.sql.expression.</tt><tt class="descname">TextAsFrom</tt><big>(</big><em>text</em>, <em>columns</em><big>)</big><a class="headerlink" href="#sqlalchemy.sql.expression.TextAsFrom" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase" title="sqlalchemy.sql.expression.SelectBase"><tt class="xref py py-class docutils literal"><span class="pre">sqlalchemy.sql.expression.SelectBase</span></tt></a></p>
<p>Wrap a <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.TextClause" title="sqlalchemy.sql.expression.TextClause"><tt class="xref py py-class docutils literal"><span class="pre">TextClause</span></tt></a> construct within a <a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase" title="sqlalchemy.sql.expression.SelectBase"><tt class="xref py py-class docutils literal"><span class="pre">SelectBase</span></tt></a>
interface.</p>
<p>This allows the <a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.TextClause" title="sqlalchemy.sql.expression.TextClause"><tt class="xref py py-class docutils literal"><span class="pre">TextClause</span></tt></a> object to gain a <tt class="docutils literal"><span class="pre">.c</span></tt> collection
and other FROM-like capabilities such as <a class="reference internal" href="#sqlalchemy.sql.expression.FromClause.alias" title="sqlalchemy.sql.expression.FromClause.alias"><tt class="xref py py-meth docutils literal"><span class="pre">FromClause.alias()</span></tt></a>,
<a class="reference internal" href="#sqlalchemy.sql.expression.SelectBase.cte" title="sqlalchemy.sql.expression.SelectBase.cte"><tt class="xref py py-meth docutils literal"><span class="pre">SelectBase.cte()</span></tt></a>, etc.</p>
<p>The <a class="reference internal" href="#sqlalchemy.sql.expression.TextAsFrom" title="sqlalchemy.sql.expression.TextAsFrom"><tt class="xref py py-class docutils literal"><span class="pre">TextAsFrom</span></tt></a> construct is produced via the
<a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.TextClause.columns" title="sqlalchemy.sql.expression.TextClause.columns"><tt class="xref py py-meth docutils literal"><span class="pre">TextClause.columns()</span></tt></a> method - see that method for details.</p>
<div class="versionadded">
<p><span>New in version 0.9.0.</span></p>
</div>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p><a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.text" title="sqlalchemy.sql.expression.text"><tt class="xref py py-func docutils literal"><span class="pre">text()</span></tt></a></p>
<p class="last"><a class="reference internal" href="sqlelement.html#sqlalchemy.sql.expression.TextClause.columns" title="sqlalchemy.sql.expression.TextClause.columns"><tt class="xref py py-meth docutils literal"><span class="pre">TextClause.columns()</span></tt></a></p>
</div>
</dd></dl>
</div>
</div>
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