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<li class="toctree-l2"><a class="reference internal" href="#explanation">Explanation</a></li>
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<section id="best-practice">
<h1>Best Practice<a class="headerlink" href="#best-practice" title="Link to this heading"></a></h1>
<section id="explanation">
<h2>Explanation<a class="headerlink" href="#explanation" title="Link to this heading"></a></h2>
<p>Because SQLite keeps very strong backwards compatibility, there are
several quirks and settings improvements that are not automatically
done. This module does them for you, and keeps up to date with SQLite
best practises. Several are described in the <a class="reference external" href="https://www.sqlite.org/quirks.html">SQLite documentation</a>.</p>
<p>Functions whose name begin with <code class="code docutils literal notranslate"><span class="pre">library</span></code> apply to the SQLite
library as a whole, while those with <code class="code docutils literal notranslate"><span class="pre">connection</span></code> apply to
individual connections.</p>
<p>You can call the individual functions, or
<a class="reference internal" href="#apsw.bestpractice.apply" title="apsw.bestpractice.apply"><code class="xref py py-func docutils literal notranslate"><span class="pre">apsw.bestpractice.apply()</span></code></a> to apply several.
<a class="reference internal" href="#apsw.bestpractice.apply" title="apsw.bestpractice.apply"><code class="xref py py-func docutils literal notranslate"><span class="pre">apply()</span></code></a> will setup
<a class="reference internal" href="apsw.html#apsw.connection_hooks" title="apsw.connection_hooks"><code class="xref py py-attr docutils literal notranslate"><span class="pre">apsw.connection_hooks</span></code></a> to affect future <a class="reference internal" href="connection.html#apsw.Connection" title="apsw.Connection"><code class="xref py py-class docutils literal notranslate"><span class="pre">connections</span></code></a> that are made.
<a class="reference internal" href="#apsw.bestpractice.recommended" title="apsw.bestpractice.recommended"><code class="xref py py-attr docutils literal notranslate"><span class="pre">recommended</span></code></a> is the recommended group:</p>
<div class="highlight-python notranslate"><div class="highlight"><pre><span></span><span class="kn">import</span> <span class="nn">apsw.bestpractice</span>
<span class="n">apsw</span><span class="o">.</span><span class="n">bestpractice</span><span class="o">.</span><span class="n">apply</span><span class="p">(</span><span class="n">apsw</span><span class="o">.</span><span class="n">bestpractice</span><span class="o">.</span><span class="n">recommended</span><span class="p">)</span>
</pre></div>
</div>
</section>
<section id="module-apsw.bestpractice">
<span id="api"></span><h2>API<a class="headerlink" href="#module-apsw.bestpractice" title="Link to this heading"></a></h2>
<p>Ensure SQLite usage prevents common mistakes, and get best performance.</p>
<dl class="py function">
<dt class="sig sig-object py" id="apsw.bestpractice.apply">
<span class="sig-prename descclassname"><span class="pre">apsw.bestpractice.</span></span><span class="sig-name descname"><span class="pre">apply</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">which</span></span><span class="p"><span class="pre">:</span></span><span class="w"> </span><span class="n"><a class="reference external" href="https://docs.python.org/3/library/stdtypes.html#tuple" title="(in Python v3.12)"><span class="pre">tuple</span></a><span class="p"><span class="pre">[</span></span><a class="reference external" href="https://docs.python.org/3/library/typing.html#typing.Callable" title="(in Python v3.12)"><span class="pre">Callable</span></a><span class="p"><span class="pre">,</span></span><span class="w"> </span><span class="p"><span class="pre">...</span></span><span class="p"><span class="pre">]</span></span></span></em><span class="sig-paren">)</span> <span class="sig-return"><span class="sig-return-icon">→</span> <span class="sig-return-typehint"><a class="reference external" href="https://docs.python.org/3/library/constants.html#None" title="(in Python v3.12)"><span class="pre">None</span></a></span></span><a class="reference internal" href="_modules/apsw/bestpractice.html#apply"><span class="viewcode-link"><span class="pre">[source]</span></span></a><a class="headerlink" href="#apsw.bestpractice.apply" title="Link to this definition"></a></dt>
<dd><p>Applies library immediately and connection to new connections</p>
</dd></dl>
<dl class="py function">
<dt class="sig sig-object py" id="apsw.bestpractice.connection_busy_timeout">
<span class="sig-prename descclassname"><span class="pre">apsw.bestpractice.</span></span><span class="sig-name descname"><span class="pre">connection_busy_timeout</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">connection</span></span><span class="p"><span class="pre">:</span></span><span class="w"> </span><span class="n"><a class="reference internal" href="connection.html#apsw.Connection" title="apsw.Connection"><span class="pre">Connection</span></a></span></em>, <em class="sig-param"><span class="n"><span class="pre">duration_ms</span></span><span class="p"><span class="pre">:</span></span><span class="w"> </span><span class="n"><a class="reference external" href="https://docs.python.org/3/library/functions.html#int" title="(in Python v3.12)"><span class="pre">int</span></a></span><span class="w"> </span><span class="o"><span class="pre">=</span></span><span class="w"> </span><span class="default_value"><span class="pre">100</span></span></em><span class="sig-paren">)</span> <span class="sig-return"><span class="sig-return-icon">→</span> <span class="sig-return-typehint"><a class="reference external" href="https://docs.python.org/3/library/constants.html#None" title="(in Python v3.12)"><span class="pre">None</span></a></span></span><a class="reference internal" href="_modules/apsw/bestpractice.html#connection_busy_timeout"><span class="viewcode-link"><span class="pre">[source]</span></span></a><a class="headerlink" href="#apsw.bestpractice.connection_busy_timeout" title="Link to this definition"></a></dt>
<dd><p>Sets a short busy timeout</p>
<dl class="field-list simple">
<dt class="field-odd">Parameters<span class="colon">:</span></dt>
<dd class="field-odd"><p><strong>duration_ms</strong> – How many thousandths of a second to wait</p>
</dd>
</dl>
<p>When another thread or process has locked the database, SQLite
immediately raises <a class="reference internal" href="exceptions.html#apsw.BusyError" title="apsw.BusyError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">apsw.BusyError</span></code></a>. Changing the <a class="reference external" href="https://www.sqlite.org/c3ref/busy_timeout.html">busy
timeout</a> gives
a grace period during which SQLite retries.</p>
</dd></dl>
<dl class="py function">
<dt class="sig sig-object py" id="apsw.bestpractice.connection_dqs">
<span class="sig-prename descclassname"><span class="pre">apsw.bestpractice.</span></span><span class="sig-name descname"><span class="pre">connection_dqs</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">connection</span></span><span class="p"><span class="pre">:</span></span><span class="w"> </span><span class="n"><a class="reference internal" href="connection.html#apsw.Connection" title="apsw.Connection"><span class="pre">Connection</span></a></span></em><span class="sig-paren">)</span> <span class="sig-return"><span class="sig-return-icon">→</span> <span class="sig-return-typehint"><a class="reference external" href="https://docs.python.org/3/library/constants.html#None" title="(in Python v3.12)"><span class="pre">None</span></a></span></span><a class="reference internal" href="_modules/apsw/bestpractice.html#connection_dqs"><span class="viewcode-link"><span class="pre">[source]</span></span></a><a class="headerlink" href="#apsw.bestpractice.connection_dqs" title="Link to this definition"></a></dt>
<dd><p>Double quotes are for identifiers only, not strings</p>
<p>Turns off <a class="reference external" href="https://www.sqlite.org/quirks.html#dblquote">allowing double quoted strings</a> if they don’t
match any identifier (column/table names etc), making it an error
to use double quotes around strings. SQL strings use single
quotes.</p>
</dd></dl>
<dl class="py function">
<dt class="sig sig-object py" id="apsw.bestpractice.connection_enable_foreign_keys">
<span class="sig-prename descclassname"><span class="pre">apsw.bestpractice.</span></span><span class="sig-name descname"><span class="pre">connection_enable_foreign_keys</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">connection</span></span><span class="p"><span class="pre">:</span></span><span class="w"> </span><span class="n"><a class="reference internal" href="connection.html#apsw.Connection" title="apsw.Connection"><span class="pre">Connection</span></a></span></em><span class="sig-paren">)</span> <span class="sig-return"><span class="sig-return-icon">→</span> <span class="sig-return-typehint"><a class="reference external" href="https://docs.python.org/3/library/constants.html#None" title="(in Python v3.12)"><span class="pre">None</span></a></span></span><a class="reference internal" href="_modules/apsw/bestpractice.html#connection_enable_foreign_keys"><span class="viewcode-link"><span class="pre">[source]</span></span></a><a class="headerlink" href="#apsw.bestpractice.connection_enable_foreign_keys" title="Link to this definition"></a></dt>
<dd><p>Enables foreign key constraints</p>
<p><a class="reference external" href="https://www.sqlite.org/foreignkeys.html">Foreign keys</a> need to
<a class="reference external" href="https://www.sqlite.org/foreignkeys.html#fk_enable">be enabled</a>
to have an effect.</p>
</dd></dl>
<dl class="py function">
<dt class="sig sig-object py" id="apsw.bestpractice.connection_wal">
<span class="sig-prename descclassname"><span class="pre">apsw.bestpractice.</span></span><span class="sig-name descname"><span class="pre">connection_wal</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">connection</span></span><span class="p"><span class="pre">:</span></span><span class="w"> </span><span class="n"><a class="reference internal" href="connection.html#apsw.Connection" title="apsw.Connection"><span class="pre">Connection</span></a></span></em><span class="sig-paren">)</span> <span class="sig-return"><span class="sig-return-icon">→</span> <span class="sig-return-typehint"><a class="reference external" href="https://docs.python.org/3/library/constants.html#None" title="(in Python v3.12)"><span class="pre">None</span></a></span></span><a class="reference internal" href="_modules/apsw/bestpractice.html#connection_wal"><span class="viewcode-link"><span class="pre">[source]</span></span></a><a class="headerlink" href="#apsw.bestpractice.connection_wal" title="Link to this definition"></a></dt>
<dd><p>Turns on write ahead logging</p>
<p>Reduces contention and improves write performance. WAL is
<a class="reference external" href="https://www.sqlite.org/wal.html">described here</a>.</p>
</dd></dl>
<dl class="py function">
<dt class="sig sig-object py" id="apsw.bestpractice.library_logging">
<span class="sig-prename descclassname"><span class="pre">apsw.bestpractice.</span></span><span class="sig-name descname"><span class="pre">library_logging</span></span><span class="sig-paren">(</span><span class="sig-paren">)</span> <span class="sig-return"><span class="sig-return-icon">→</span> <span class="sig-return-typehint"><a class="reference external" href="https://docs.python.org/3/library/constants.html#None" title="(in Python v3.12)"><span class="pre">None</span></a></span></span><a class="reference internal" href="_modules/apsw/bestpractice.html#library_logging"><span class="viewcode-link"><span class="pre">[source]</span></span></a><a class="headerlink" href="#apsw.bestpractice.library_logging" title="Link to this definition"></a></dt>
<dd><p>Forwards SQLite logging to Python logging module</p>
<p>See <a class="reference internal" href="ext.html#apsw.ext.log_sqlite" title="apsw.ext.log_sqlite"><code class="xref py py-meth docutils literal notranslate"><span class="pre">apsw.ext.log_sqlite()</span></code></a></p>
</dd></dl>
<dl class="py data">
<dt class="sig sig-object py" id="apsw.bestpractice.recommended">
<span class="sig-prename descclassname"><span class="pre">apsw.bestpractice.</span></span><span class="sig-name descname"><span class="pre">recommended</span></span><em class="property"><span class="p"><span class="pre">:</span></span><span class="w"> </span><a class="reference external" href="https://docs.python.org/3/library/stdtypes.html#tuple" title="(in Python v3.12)"><span class="pre">tuple</span></a><span class="p"><span class="pre">[</span></span><a class="reference external" href="https://docs.python.org/3/library/typing.html#typing.Callable" title="(in Python v3.12)"><span class="pre">Callable</span></a><span class="p"><span class="pre">,</span></span><span class="w"> </span><span class="p"><span class="pre">...</span></span><span class="p"><span class="pre">]</span></span></em><em class="property"><span class="w"> </span><span class="p"><span class="pre">=</span></span><span class="w"> </span><span class="pre">(<function</span> <span class="pre">connection_wal>,</span> <span class="pre"><function</span> <span class="pre">connection_busy_timeout>,</span> <span class="pre"><function</span> <span class="pre">connection_enable_foreign_keys>,</span> <span class="pre"><function</span> <span class="pre">connection_dqs>,</span> <span class="pre"><function</span> <span class="pre">library_logging>)</span></em><a class="headerlink" href="#apsw.bestpractice.recommended" title="Link to this definition"></a></dt>
<dd><p>All of them</p>
</dd></dl>
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