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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>F.6. btree_gin</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 V1.79.1" /><link rel="prev" href="bloom.html" title="F.5. bloom" /><link rel="next" href="btree-gist.html" title="F.7. btree_gist" /></head><body><div xmlns="http://www.w3.org/TR/xhtml1/transitional" class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">F.6. btree_gin</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="bloom.html" title="F.5. bloom">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="contrib.html" title="Appendix F. Additional Supplied Modules">Up</a></td><th width="60%" align="center">Appendix F. Additional Supplied Modules</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 12.4 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="btree-gist.html" title="F.7. btree_gist">Next</a></td></tr></table><hr></hr></div><div class="sect1" id="BTREE-GIN"><div class="titlepage"><div><div><h2 class="title" style="clear: both">F.6. btree_gin</h2></div></div></div><div class="toc"><dl class="toc"><dt><span class="sect2"><a href="btree-gin.html#id-1.11.7.15.5">F.6.1. Example Usage</a></span></dt><dt><span class="sect2"><a href="btree-gin.html#id-1.11.7.15.6">F.6.2. Authors</a></span></dt></dl></div><a id="id-1.11.7.15.2" class="indexterm"></a><p>
  <code class="filename">btree_gin</code> provides sample GIN operator classes that
  implement B-tree equivalent behavior for the data types
  <code class="type">int2</code>, <code class="type">int4</code>, <code class="type">int8</code>, <code class="type">float4</code>,
  <code class="type">float8</code>, <code class="type">timestamp with time zone</code>,
  <code class="type">timestamp without time zone</code>, <code class="type">time with time zone</code>,
  <code class="type">time without time zone</code>, <code class="type">date</code>, <code class="type">interval</code>,
  <code class="type">oid</code>, <code class="type">money</code>, <code class="type">"char"</code>,
  <code class="type">varchar</code>, <code class="type">text</code>, <code class="type">bytea</code>, <code class="type">bit</code>,
  <code class="type">varbit</code>, <code class="type">macaddr</code>, <code class="type">macaddr8</code>, <code class="type">inet</code>,
  <code class="type">cidr</code>, <code class="type">uuid</code>, <code class="type">name</code>, <code class="type">bool</code>,
  <code class="type">bpchar</code>, and all <code class="type">enum</code> types.
 </p><p>
  In general, these operator classes will not outperform the equivalent
  standard B-tree index methods, and they lack one major feature of the
  standard B-tree code: the ability to enforce uniqueness.  However,
  they are useful for GIN testing and as a base for developing other
  GIN operator classes.  Also, for queries that test both a GIN-indexable
  column and a B-tree-indexable column, it might be more efficient to create
  a multicolumn GIN index that uses one of these operator classes than to create
  two separate indexes that would have to be combined via bitmap ANDing.
 </p><div class="sect2" id="id-1.11.7.15.5"><div class="titlepage"><div><div><h3 class="title">F.6.1. Example Usage</h3></div></div></div><pre class="programlisting">
CREATE TABLE test (a int4);
-- create index
CREATE INDEX testidx ON test USING GIN (a);
-- query
SELECT * FROM test WHERE a &lt; 10;
</pre></div><div class="sect2" id="id-1.11.7.15.6"><div class="titlepage"><div><div><h3 class="title">F.6.2. Authors</h3></div></div></div><p>
   Teodor Sigaev (<code class="email">&lt;<a class="email" href="mailto:teodor@stack.net">teodor@stack.net</a>&gt;</code>) and
   Oleg Bartunov (<code class="email">&lt;<a class="email" href="mailto:oleg@sai.msu.su">oleg@sai.msu.su</a>&gt;</code>).  See
   <a class="ulink" href="http://www.sai.msu.su/~megera/oddmuse/index.cgi/Gin" target="_top">http://www.sai.msu.su/~megera/oddmuse/index.cgi/Gin</a>
   for additional information.
  </p></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="bloom.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="contrib.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="btree-gist.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">F.5. bloom </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> F.7. btree_gist</td></tr></table></div></body></html>