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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>9.14. UUID Functions</title><link rel="stylesheet" type="text/css" href="stylesheet.css" /><link rev="made" href="pgsql-docs@lists.postgresql.org" /><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" /><link rel="prev" href="functions-textsearch.html" title="9.13. Text Search Functions and Operators" /><link rel="next" href="functions-xml.html" title="9.15. XML Functions" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">9.14. UUID Functions</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="functions-textsearch.html" title="9.13. Text Search Functions and Operators">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="functions.html" title="Chapter 9. Functions and Operators">Up</a></td><th width="60%" align="center">Chapter 9. Functions and Operators</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 18.4 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="functions-xml.html" title="9.15. XML Functions">Next</a></td></tr></table><hr /></div><div class="sect1" id="FUNCTIONS-UUID"><div class="titlepage"><div><div><h2 class="title" style="clear: both">9.14. UUID Functions <a href="#FUNCTIONS-UUID" class="id_link">#</a></h2></div></div></div><a id="id-1.5.8.20.2" class="indexterm"></a><a id="id-1.5.8.20.3" class="indexterm"></a><a id="id-1.5.8.20.4" class="indexterm"></a><a id="id-1.5.8.20.5" class="indexterm"></a><a id="id-1.5.8.20.6" class="indexterm"></a><a id="id-1.5.8.20.7" class="indexterm"></a><p>
   <a class="xref" href="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 class="table" summary="UUID Generation Functions" border="1"><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></tbody></table></div></div><br class="table-break" /><div class="note"><h3 class="title">Note</h3><p>
    The <a class="xref" href="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="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 class="table" summary="UUID Extraction Functions" border="1"><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="https://datatracker.ietf.org/doc/html/rfc9562" 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="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="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></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="functions-textsearch.html" title="9.13. Text Search Functions and Operators">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="functions.html" title="Chapter 9. Functions and Operators">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="functions-xml.html" title="9.15. XML Functions">Next</a></td></tr><tr><td width="40%" align="left" valign="top">9.13. Text Search Functions and Operators </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 18.4 Documentation">Home</a></td><td width="40%" align="right" valign="top"> 9.15. XML Functions</td></tr></table></div></body></html>