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   2 <!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 18.0 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>
   3    <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>
   4    functions that can be used to generate UUIDs.
   5   </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">
   6        <p class="func_signature">
   7         Function
   8        </p>
   9        <p>
  10         Description
  11         </p>
  12        <p>
  13         Example(s)
  14        </p>
  15        </th></tr></thead><tbody><tr><td class="func_table_entry">
  16        <p class="func_signature">
  17         <code class="type">gen_random_uuid</code>
  18         → <code class="returnvalue">uuid</code>
  19        </p>
  20        <p class="func_signature">
  21         <code class="type">uuidv4</code>
  22         → <code class="returnvalue">uuid</code>
  23        </p>
  24        <p>
  25          Generate a version 4 (random) UUID.
  26        </p>
  27        <p>
  28         <code class="literal">gen_random_uuid()</code>
  29         → <code class="returnvalue">5b30857f-0bfa-48b5-ac0b-5c64e28078d1</code>
  30        </p>
  31        <p>
  32         <code class="literal">uuidv4()</code>
  33         → <code class="returnvalue">b42410ee-132f-42ee-9e4f-09a6485c95b8</code>
  34        </p>
  35       </td></tr><tr><td class="func_table_entry">
  36        <p class="func_signature">
  37         <code class="type">uuidv7</code>
  38         ( [<span class="optional"> <em class="parameter"><code>shift</code></em> <code class="type">interval</code> </span>] )
  39         → <code class="returnvalue">uuid</code>
  40        </p>
  41        <p>
  42         Generate a version 7 (time-ordered) UUID. The timestamp is computed using UNIX timestamp
  43         with millisecond precision + sub-millisecond timestamp + random. The optional parameter
  44         <em class="parameter"><code>shift</code></em> will shift the computed timestamp by the given <code class="type">interval</code>.
  45        </p>
  46        <p>
  47         <code class="literal">uuidv7()</code>
  48         → <code class="returnvalue">019535d9-3df7-79fb-b466-fa907fa17f9e</code>
  49        </p>
  50       </td></tr></tbody></table></div></div><br class="table-break" /><div class="note"><h3 class="title">Note</h3><p>
  51     The <a class="xref" href="uuid-ossp.html" title="F.49. uuid-ossp — a UUID generator">uuid-ossp</a> module provides additional functions that
  52     implement other standard algorithms for generating UUIDs.
  53    </p></div><p>
  54    <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>
  55    functions that can be used to extract information from UUIDs.
  56   </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">
  57        <p class="func_signature">
  58         Function
  59        </p>
  60        <p>
  61         Description
  62        </p>
  63        <p>
  64         Example(s)
  65        </p>
  66       </th></tr></thead><tbody><tr><td class="func_table_entry">
  67        <p class="func_signature">
  68         <code class="type">uuid_extract_timestamp</code>
  69         ( <code class="type">uuid</code> )
  70         → <code class="returnvalue">timestamp with time zone</code>
  71        </p>
  72        <p>
  73         Extracts a <code class="type">timestamp with time zone</code> from UUID
  74         version 1 and 7.  For other versions, this function returns null.  Note that
  75         the extracted timestamp is not necessarily exactly equal to the time the
  76         UUID was generated; this depends on the implementation that generated the
  77         UUID.
  78        </p>
  79        <p>
  80         <code class="literal">uuid_extract_timestamp('019535d9-3df7-79fb-b466-fa907fa17f9e'::uuid)</code>
  81          → <code class="returnvalue">2025-02-23 21:46:24.503-05</code>
  82        </p>
  83       </td></tr><tr><td class="func_table_entry">
  84        <p class="func_signature">
  85         <code class="type">uuid_extract_version</code>
  86         ( <code class="type">uuid</code> )
  87         → <code class="returnvalue">smallint</code>
  88        </p>
  89        <p>
  90         Extracts the version from a UUID of the variant described by
  91         <a class="ulink" href="https://datatracker.ietf.org/doc/html/rfc9562" target="_top">RFC 9562</a>.  For
  92         other variants, this function returns null.  For example, for a UUID
  93         generated by <code class="function">gen_random_uuid</code>, this function will
  94         return 4.
  95        </p>
  96        <p>
  97         <code class="literal">uuid_extract_version('41db1265-8bc1-4ab3-992f-885799a4af1d'::uuid)</code>
  98         → <code class="returnvalue">4</code>
  99        </p>
 100        <p>
 101         <code class="literal">uuid_extract_version('019535d9-3df7-79fb-b466-fa907fa17f9e'::uuid)</code>
 102         → <code class="returnvalue">7</code>
 103        </p>
 104       </td></tr></tbody></table></div></div><br class="table-break" /><p>
 105    <span class="productname">PostgreSQL</span> also provides the usual comparison
 106    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
 107    UUIDs.
 108   </p><p>
 109    See <a class="xref" href="datatype-uuid.html" title="8.12. UUID Type">Section 8.12</a> for details on the data type
 110    <code class="type">uuid</code> in <span class="productname">PostgreSQL</span>.
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