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<li class="toctree-l2"><a class="reference internal" href="#zeroblob-class">zeroblob class</a><ul>
<li class="toctree-l3"><a class="reference internal" href="#apsw.zeroblob"><code class="docutils literal notranslate"><span class="pre">zeroblob</span></code></a><ul>
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<li class="toctree-l2"><a class="reference internal" href="#blob-class">Blob class</a><ul>
<li class="toctree-l3"><a class="reference internal" href="#apsw.Blob"><code class="docutils literal notranslate"><span class="pre">Blob</span></code></a><ul>
<li class="toctree-l4"><a class="reference internal" href="#apsw.Blob.__enter__"><code class="docutils literal notranslate"><span class="pre">Blob.__enter__()</span></code></a></li>
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<section id="blob-input-output">
<span id="blobio"></span><h1>Blob Input/Output<a class="headerlink" href="#blob-input-output" title="Link to this heading"></a></h1>
<p>A <a class="reference external" href="https://en.wikipedia.org/wiki/Binary_large_object">blob</a> is a
SQLite <a class="reference external" href="https://sqlite.org/datatype3.html">datatype</a> representing
a sequence of bytes. It can be zero or more bytes in size. Blobs
cannot be resized, but you can read and overwrite parts of them.</p>
<p>SQLite blobs have an absolute maximum size of 2GB and a <a class="reference external" href="https://sqlite.org/c3ref/c_limit_attached.html">default
maximum size</a> of
1GB.</p>
<p>An alternate approach to using blobs is to store the data in files and
store the filename in the database. Doing so loses the <a class="reference external" href="https://sqlite.org/transactional.html">ACID</a> properties of SQLite.
There are <a class="reference external" href="https://www.sqlite.org/fasterthanfs.html">benchmarks</a>.</p>
<section id="zeroblob-class">
<h2>zeroblob class<a class="headerlink" href="#zeroblob-class" title="Link to this heading"></a></h2>
<dl class="py class">
<dt class="sig sig-object py" id="apsw.zeroblob">
<em class="property"><span class="pre">class</span><span class="w"> </span></em><span class="sig-prename descclassname"><span class="pre">apsw.</span></span><span class="sig-name descname"><span class="pre">zeroblob</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">size</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></em><span class="sig-paren">)</span><a class="headerlink" href="#apsw.zeroblob" title="Link to this definition"></a></dt>
<dd><p>If you want to insert a blob into a row, you need to
supply the entire blob in one go. Using this class or
<a class="reference external" href="https://www.sqlite.org/lang_corefunc.html#zeroblob">function</a>
allocates the space in the database filling it with zeroes.</p>
<p>You can then overwrite parts in smaller chunks, without having
to do it all at once. The <a class="reference internal" href="example.html#example-blob-io"><span class="std std-ref">example</span></a> shows
how to use it.</p>
<dl class="field-list simple">
<dt class="field-odd">Parameters<span class="colon">:</span></dt>
<dd class="field-odd"><p><strong>size</strong> – Number of zeroed bytes to create</p>
</dd>
</dl>
</dd></dl>
<dl class="py method">
<dt class="sig sig-object py" id="apsw.zeroblob.length">
<span class="sig-prename descclassname"><span class="pre">zeroblob.</span></span><span class="sig-name descname"><span class="pre">length</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/functions.html#int" title="(in Python v3.12)"><span class="pre">int</span></a></span></span><a class="headerlink" href="#apsw.zeroblob.length" title="Link to this definition"></a></dt>
<dd><p>Size of zero blob in bytes.</p>
</dd></dl>
</section>
<section id="blob-class">
<h2>Blob class<a class="headerlink" href="#blob-class" title="Link to this heading"></a></h2>
<dl class="py class">
<dt class="sig sig-object py" id="apsw.Blob">
<em class="property"><span class="pre">class</span><span class="w"> </span></em><span class="sig-prename descclassname"><span class="pre">apsw.</span></span><span class="sig-name descname"><span class="pre">Blob</span></span><a class="headerlink" href="#apsw.Blob" title="Link to this definition"></a></dt>
<dd><p>This object is created by <a class="reference internal" href="connection.html#apsw.Connection.blob_open" title="apsw.Connection.blob_open"><code class="xref py py-meth docutils literal notranslate"><span class="pre">Connection.blob_open()</span></code></a> and provides
access to a blob in the database. It behaves like a Python file.
It wraps a <a class="reference external" href="https://sqlite.org/c3ref/blob.html">sqlite3_blob</a>.</p>
<div class="admonition note">
<p class="admonition-title">Note</p>
<p>You cannot change the size of a blob using this object. You should
create it with the correct size in advance either by using
<a class="reference internal" href="#apsw.zeroblob" title="apsw.zeroblob"><code class="xref py py-class docutils literal notranslate"><span class="pre">zeroblob</span></code></a> or the <a class="reference external" href="https://sqlite.org/lang_corefunc.html">zeroblob()</a> function.</p>
</div>
<p>See the <a class="reference internal" href="example.html#example-blob-io"><span class="std std-ref">example</span></a>.</p>
</dd></dl>
<dl class="py method">
<dt class="sig sig-object py" id="apsw.Blob.__enter__">
<span class="sig-prename descclassname"><span class="pre">Blob.</span></span><span class="sig-name descname"><span class="pre">__enter__</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 internal" href="#apsw.Blob" title="apsw.Blob"><span class="pre">Blob</span></a></span></span><a class="headerlink" href="#apsw.Blob.__enter__" title="Link to this definition"></a></dt>
<dd><p>You can use a blob as a <a class="reference external" href="https://docs.python.org/3/reference/datamodel.html#with-statement-context-managers">context manager</a>
as defined in <span class="target" id="index-0"></span><a class="pep reference external" href="https://peps.python.org/pep-0343/"><strong>PEP 0343</strong></a>. When you use <em>with</em> statement,
the blob is always <a class="reference internal" href="#apsw.Blob.close" title="apsw.Blob.close"><code class="xref py py-meth docutils literal notranslate"><span class="pre">closed</span></code></a> on exit from the block, even if an
exception occurred in the block.</p>
<p>For example:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="k">with</span> <span class="n">connection</span><span class="o">.</span><span class="n">blob_open</span><span class="p">()</span> <span class="k">as</span> <span class="n">blob</span><span class="p">:</span>
<span class="n">blob</span><span class="o">.</span><span class="n">write</span><span class="p">(</span><span class="s2">"..."</span><span class="p">)</span>
<span class="n">res</span><span class="o">=</span><span class="n">blob</span><span class="o">.</span><span class="n">read</span><span class="p">(</span><span class="mi">1024</span><span class="p">)</span>
</pre></div>
</div>
</dd></dl>
<dl class="py method">
<dt class="sig sig-object py" id="apsw.Blob.__exit__">
<span class="sig-prename descclassname"><span class="pre">Blob.</span></span><span class="sig-name descname"><span class="pre">__exit__</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">etype</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#type" title="(in Python v3.12)"><span class="pre">type</span></a><span class="p"><span class="pre">[</span></span><a class="reference external" href="https://docs.python.org/3/library/exceptions.html#BaseException" title="(in Python v3.12)"><span class="pre">BaseException</span></a><span class="p"><span class="pre">]</span></span><span class="w"> </span><span class="p"><span class="pre">|</span></span><span class="w"> </span><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></em>, <em class="sig-param"><span class="n"><span class="pre">evalue</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/exceptions.html#BaseException" title="(in Python v3.12)"><span class="pre">BaseException</span></a><span class="w"> </span><span class="p"><span class="pre">|</span></span><span class="w"> </span><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></em>, <em class="sig-param"><span class="n"><span class="pre">etraceback</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/types.html#types.TracebackType" title="(in Python v3.12)"><span class="pre">types.TracebackType</span></a><span class="w"> </span><span class="p"><span class="pre">|</span></span><span class="w"> </span><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></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/functions.html#bool" title="(in Python v3.12)"><span class="pre">bool</span></a><span class="w"> </span><span class="p"><span class="pre">|</span></span><span class="w"> </span><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="headerlink" href="#apsw.Blob.__exit__" title="Link to this definition"></a></dt>
<dd><p>Implements context manager in conjunction with
<a class="reference internal" href="#apsw.Blob.__enter__" title="apsw.Blob.__enter__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__enter__()</span></code></a>. Any exception that happened in the
<em>with</em> block is raised after closing the blob.</p>
</dd></dl>
<dl class="py method" id="index-1">
<dt class="sig sig-object py" id="apsw.Blob.close">
<span class="sig-prename descclassname"><span class="pre">Blob.</span></span><span class="sig-name descname"><span class="pre">close</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">force</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#bool" title="(in Python v3.12)"><span class="pre">bool</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">False</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="headerlink" href="#apsw.Blob.close" title="Link to this definition"></a></dt>
<dd><p>Closes the blob. Note that even if an error occurs the blob is
still closed.</p>
<div class="admonition note">
<p class="admonition-title">Note</p>
<p>In some cases errors that technically occurred in the
<a class="reference internal" href="#apsw.Blob.read" title="apsw.Blob.read"><code class="xref py py-meth docutils literal notranslate"><span class="pre">read()</span></code></a> and <a class="reference internal" href="#apsw.Blob.write" title="apsw.Blob.write"><code class="xref py py-meth docutils literal notranslate"><span class="pre">write()</span></code></a> routines may not be
reported until close is called. Similarly errors that occurred
in those methods (eg calling <a class="reference internal" href="#apsw.Blob.write" title="apsw.Blob.write"><code class="xref py py-meth docutils literal notranslate"><span class="pre">write()</span></code></a> on a read-only
blob) may also be re-reported in <a class="reference internal" href="#apsw.Blob.close" title="apsw.Blob.close"><code class="xref py py-meth docutils literal notranslate"><span class="pre">close()</span></code></a>. (This
behaviour is what the underlying SQLite APIs do - it is not APSW
doing it.)</p>
</div>
<p>It is okay to call <a class="reference internal" href="#apsw.Blob.close" title="apsw.Blob.close"><code class="xref py py-meth docutils literal notranslate"><span class="pre">close()</span></code></a> multiple times.</p>
<dl class="field-list simple">
<dt class="field-odd">Parameters<span class="colon">:</span></dt>
<dd class="field-odd"><p><strong>force</strong> – Ignores any errors during close.</p>
</dd>
</dl>
<p>Calls: <a class="reference external" href="https://sqlite.org/c3ref/blob_close.html">sqlite3_blob_close</a></p>
</dd></dl>
<dl class="py method" id="index-2">
<dt class="sig sig-object py" id="apsw.Blob.length">
<span class="sig-prename descclassname"><span class="pre">Blob.</span></span><span class="sig-name descname"><span class="pre">length</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/functions.html#int" title="(in Python v3.12)"><span class="pre">int</span></a></span></span><a class="headerlink" href="#apsw.Blob.length" title="Link to this definition"></a></dt>
<dd><p>Returns the size of the blob in bytes.</p>
<p>Calls: <a class="reference external" href="https://sqlite.org/c3ref/blob_bytes.html">sqlite3_blob_bytes</a></p>
</dd></dl>
<dl class="py method" id="index-3">
<dt class="sig sig-object py" id="apsw.Blob.read">
<span class="sig-prename descclassname"><span class="pre">Blob.</span></span><span class="sig-name descname"><span class="pre">read</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">length</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">-1</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/stdtypes.html#bytes" title="(in Python v3.12)"><span class="pre">bytes</span></a></span></span><a class="headerlink" href="#apsw.Blob.read" title="Link to this definition"></a></dt>
<dd><p>Reads amount of data requested, or till end of file, whichever is
earlier. Attempting to read beyond the end of the blob returns an
empty bytes in the same manner as end of file on normal file
objects. Negative numbers read all remaining data.</p>
<p>Calls: <a class="reference external" href="https://sqlite.org/c3ref/blob_read.html">sqlite3_blob_read</a></p>
</dd></dl>
<dl class="py method" id="index-4">
<dt class="sig sig-object py" id="apsw.Blob.read_into">
<span class="sig-prename descclassname"><span class="pre">Blob.</span></span><span class="sig-name descname"><span class="pre">read_into</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">buffer</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#bytearray" title="(in Python v3.12)"><span class="pre">bytearray</span></a><span class="w"> </span><span class="p"><span class="pre">|</span></span><span class="w"> </span><a class="reference external" href="https://docs.python.org/3/library/array.html#array.array" title="(in Python v3.12)"><span class="pre">array.array</span></a><span class="p"><span class="pre">[</span></span><span class="pre">Any</span><span class="p"><span class="pre">]</span></span><span class="w"> </span><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#memoryview" title="(in Python v3.12)"><span class="pre">memoryview</span></a></span></em>, <em class="sig-param"><span class="n"><span class="pre">offset</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">0</span></span></em>, <em class="sig-param"><span class="n"><span class="pre">length</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">-1</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="headerlink" href="#apsw.Blob.read_into" title="Link to this definition"></a></dt>
<dd><p>Reads from the blob into a buffer you have supplied. This method is
useful if you already have a buffer like object that data is being
assembled in, and avoids allocating results in <a class="reference internal" href="#apsw.Blob.read" title="apsw.Blob.read"><code class="xref py py-meth docutils literal notranslate"><span class="pre">Blob.read()</span></code></a> and
then copying into buffer.</p>
<dl class="field-list simple">
<dt class="field-odd">Parameters<span class="colon">:</span></dt>
<dd class="field-odd"><ul class="simple">
<li><p><strong>buffer</strong> – A writable buffer like object.
There is a <a class="reference external" href="https://docs.python.org/3/library/stdtypes.html#bytearray" title="(in Python v3.12)"><code class="xref py py-class docutils literal notranslate"><span class="pre">bytearray</span></code></a> type that is very useful.
<a class="reference external" href="https://docs.python.org/3/library/array.html#module-array" title="(in Python v3.12)"><code class="xref py py-mod docutils literal notranslate"><span class="pre">Arrays</span></code></a> also work.</p></li>
<li><p><strong>offset</strong> – The position to start writing into the buffer
defaulting to the beginning.</p></li>
<li><p><strong>length</strong> – How much of the blob to read. The default is the
remaining space left in the buffer. Note that if
there is more space available than blob left then you
will get a <em>ValueError</em> exception.</p></li>
</ul>
</dd>
</dl>
<p>Calls: <a class="reference external" href="https://sqlite.org/c3ref/blob_read.html">sqlite3_blob_read</a></p>
</dd></dl>
<dl class="py method" id="index-5">
<dt class="sig sig-object py" id="apsw.Blob.reopen">
<span class="sig-prename descclassname"><span class="pre">Blob.</span></span><span class="sig-name descname"><span class="pre">reopen</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">rowid</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></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="headerlink" href="#apsw.Blob.reopen" title="Link to this definition"></a></dt>
<dd><p>Change this blob object to point to a different row. It can be
faster than closing an existing blob an opening a new one.</p>
<p>Calls: <a class="reference external" href="https://sqlite.org/c3ref/blob_reopen.html">sqlite3_blob_reopen</a></p>
</dd></dl>
<dl class="py method">
<dt class="sig sig-object py" id="apsw.Blob.seek">
<span class="sig-prename descclassname"><span class="pre">Blob.</span></span><span class="sig-name descname"><span class="pre">seek</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">offset</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></em>, <em class="sig-param"><span class="n"><span class="pre">whence</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">0</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="headerlink" href="#apsw.Blob.seek" title="Link to this definition"></a></dt>
<dd><p>Changes current position to <em>offset</em> biased by <em>whence</em>.</p>
<dl class="field-list simple">
<dt class="field-odd">Parameters<span class="colon">:</span></dt>
<dd class="field-odd"><ul class="simple">
<li><p><strong>offset</strong> – New position to seek to. Can be positive or negative number.</p></li>
<li><p><strong>whence</strong> – Use 0 if <em>offset</em> is relative to the beginning of the blob,
1 if <em>offset</em> is relative to the current position,
and 2 if <em>offset</em> is relative to the end of the blob.</p></li>
</ul>
</dd>
<dt class="field-even">Raises<span class="colon">:</span></dt>
<dd class="field-even"><p><a class="reference external" href="https://docs.python.org/3/library/exceptions.html#ValueError" title="(in Python v3.12)"><strong>ValueError</strong></a> – If the resulting offset is before the beginning (less than zero) or beyond the end of the blob.</p>
</dd>
</dl>
</dd></dl>
<dl class="py method">
<dt class="sig sig-object py" id="apsw.Blob.tell">
<span class="sig-prename descclassname"><span class="pre">Blob.</span></span><span class="sig-name descname"><span class="pre">tell</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/functions.html#int" title="(in Python v3.12)"><span class="pre">int</span></a></span></span><a class="headerlink" href="#apsw.Blob.tell" title="Link to this definition"></a></dt>
<dd><p>Returns the current offset.</p>
</dd></dl>
<dl class="py method" id="index-6">
<dt class="sig sig-object py" id="apsw.Blob.write">
<span class="sig-prename descclassname"><span class="pre">Blob.</span></span><span class="sig-name descname"><span class="pre">write</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">data</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#bytes" title="(in Python v3.12)"><span class="pre">bytes</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="headerlink" href="#apsw.Blob.write" title="Link to this definition"></a></dt>
<dd><p>Writes the data to the blob.</p>
<dl class="field-list simple">
<dt class="field-odd">Parameters<span class="colon">:</span></dt>
<dd class="field-odd"><p><strong>data</strong> – bytes to write</p>
</dd>
<dt class="field-even">Raises<span class="colon">:</span></dt>
<dd class="field-even"><ul class="simple">
<li><p><a class="reference external" href="https://docs.python.org/3/library/exceptions.html#TypeError" title="(in Python v3.12)"><strong>TypeError</strong></a> – Wrong data type</p></li>
<li><p><a class="reference external" href="https://docs.python.org/3/library/exceptions.html#ValueError" title="(in Python v3.12)"><strong>ValueError</strong></a> – If the data would go beyond the end of the blob.
You cannot increase the size of a blob by writing beyond the end.
You need to use <a class="reference internal" href="#apsw.zeroblob" title="apsw.zeroblob"><code class="xref py py-class docutils literal notranslate"><span class="pre">zeroblob</span></code></a> to set the desired size first when
inserting the blob.</p></li>
</ul>
</dd>
</dl>
<p>Calls: <a class="reference external" href="https://sqlite.org/c3ref/blob_write.html">sqlite3_blob_write</a></p>
</dd></dl>
</section>
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