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<th align="center" colspan="5">9.14. UUID Functions</th>
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<div class="sect1" id="FUNCTIONS-UUID">
<div class="titlepage">
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<h2 class="title" style="clear: both">9.14. UUID Functions <a class="id_link" href="#FUNCTIONS-UUID">#</a></h2>
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</div><a class="indexterm" id="id-1.5.8.20.2" name="id-1.5.8.20.2"></a><a class="indexterm" id="id-1.5.8.20.3" name="id-1.5.8.20.3"></a><a class="indexterm" id="id-1.5.8.20.4" name="id-1.5.8.20.4"></a><a class="indexterm" id="id-1.5.8.20.5" name="id-1.5.8.20.5"></a><a class="indexterm" id="id-1.5.8.20.6" name="id-1.5.8.20.6"></a><a class="indexterm" id="id-1.5.8.20.7" name="id-1.5.8.20.7"></a>
<p><a class="xref" href="/docs/18/functions-uuid.html#FUNC_UUID_GEN_TABLE" title="Table 9.45. UUID Generation Functions">Table 9.45</a> shows the <span class="productname">PostgreSQL</span> functions that can be used to generate UUIDs.</p>
<div class="table" id="FUNC_UUID_GEN_TABLE">
<p class="title"><strong>Table 9.45. <acronym class="acronym">UUID</acronym> Generation Functions</strong></p>
<div class="table-contents">
<table border="1" class="table" summary="UUID Generation Functions">
<colgroup>
<col/>
</colgroup>
<thead>
<tr>
<th class="func_table_entry">
<p class="func_signature">Function</p>
<p>Description</p>
<p>Example(s)</p>
</th>
</tr>
</thead>
<tbody>
<tr>
<td class="func_table_entry">
<p class="func_signature"><code class="function">gen_random_uuid</code> ( ) → <code class="returnvalue">uuid</code></p>
<p class="func_signature"><code class="function">uuidv4</code> ( ) → <code class="returnvalue">uuid</code></p>
<p>Generates a version 4 (random) UUID</p>
<p><code class="literal">gen_random_uuid()</code> → <code class="returnvalue">5b30857f-0bfa-48b5-ac0b-5c64e28078d1</code></p>
<p><code class="literal">uuidv4()</code> → <code class="returnvalue">b42410ee-132f-42ee-9e4f-09a6485c95b8</code></p>
</td>
</tr>
<tr>
<td class="func_table_entry">
<p class="func_signature"><code class="function">uuidv7</code> ( [ <span class="optional"><em class="parameter"><code>shift</code></em> <code class="type">interval</code></span> ] ) → <code class="returnvalue">uuid</code></p>
<p>Generates a version 7 (time-ordered) UUID. The timestamp is computed using UNIX timestamp with millisecond precision + sub-millisecond timestamp + random. The optional parameter <em class="parameter"><code>shift</code></em> will shift the computed timestamp by the given <code class="type">interval</code>.</p>
<p><code class="literal">uuidv7()</code> → <code class="returnvalue">019535d9-3df7-79fb-b466-fa907fa17f9e</code></p>
</td>
</tr>
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</table>
</div>
</div><br class="table-break"/>
<div class="note">
<h3 class="title">Note</h3>
<p>The <a class="xref" href="/docs/18/uuid-ossp.html" title="F.49. uuid-ossp — a UUID generator">uuid-ossp</a> module provides additional functions that implement other standard algorithms for generating UUIDs.</p>
</div>
<p><a class="xref" href="/docs/18/functions-uuid.html#FUNC_UUID_EXTRACT_TABLE" title="Table 9.46. UUID Extraction Functions">Table 9.46</a> shows the <span class="productname">PostgreSQL</span> functions that can be used to extract information from UUIDs.</p>
<div class="table" id="FUNC_UUID_EXTRACT_TABLE">
<p class="title"><strong>Table 9.46. <acronym class="acronym">UUID</acronym> Extraction Functions</strong></p>
<div class="table-contents">
<table border="1" class="table" summary="UUID Extraction Functions">
<colgroup>
<col/>
</colgroup>
<thead>
<tr>
<th class="func_table_entry">
<p class="func_signature">Function</p>
<p>Description</p>
<p>Example(s)</p>
</th>
</tr>
</thead>
<tbody>
<tr>
<td class="func_table_entry">
<p class="func_signature"><code class="function">uuid_extract_timestamp</code> ( <code class="type">uuid</code> ) → <code class="returnvalue">timestamp with time zone</code></p>
<p>Extracts a <code class="type">timestamp with time zone</code> from a UUID of version 1 or 7. For other versions, this function returns null. Note that the extracted timestamp is not necessarily exactly equal to the time the UUID was generated; this depends on the implementation that generated the UUID.</p>
<p><code class="literal">uuid_extract_timestamp('019535d9-3df7-79fb-b466-​fa907fa17f9e'::uuid)</code> → <code class="returnvalue">2025-02-23 21:46:24.503-05</code></p>
</td>
</tr>
<tr>
<td class="func_table_entry">
<p class="func_signature"><code class="function">uuid_extract_version</code> ( <code class="type">uuid</code> ) → <code class="returnvalue">smallint</code></p>
<p>Extracts the version from a UUID of one of the variants described by <a class="ulink" href="/_404.html" target="_top">RFC 9562</a>. For other variants, this function returns null. For example, for a UUID generated by <code class="function">gen_random_uuid()</code>, this function will return 4.</p>
<p><code class="literal">uuid_extract_version('41db1265-8bc1-4ab3-992f-​885799a4af1d'::uuid)</code> → <code class="returnvalue">4</code></p>
<p><code class="literal">uuid_extract_version('019535d9-3df7-79fb-b466-​fa907fa17f9e'::uuid)</code> → <code class="returnvalue">7</code></p>
</td>
</tr>
</tbody>
</table>
</div>
</div><br class="table-break"/>
<p><span class="productname">PostgreSQL</span> also provides the usual comparison operators shown in <a class="xref" href="/docs/18/functions-comparison.html#FUNCTIONS-COMPARISON-OP-TABLE" title="Table 9.1. Comparison Operators">Table 9.1</a> for UUIDs.</p>
<p>See <a class="xref" href="/docs/18/datatype-uuid.html" title="8.12. UUID Type">Section 8.12</a> for details on the data type <code class="type">uuid</code> in <span class="productname">PostgreSQL</span>.</p>
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