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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.11. dict_int</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="contrib-dblink-build-sql-update.html" title="dblink_build_sql_update" /><link rel="next" href="dict-xsyn.html" title="F.12. dict_xsyn" /></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.11. dict_int</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="contrib-dblink-build-sql-update.html" title="dblink_build_sql_update">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="dict-xsyn.html" title="F.12. dict_xsyn">Next</a></td></tr></table><hr></hr></div><div class="sect1" id="DICT-INT"><div class="titlepage"><div><div><h2 class="title" style="clear: both">F.11. dict_int</h2></div></div></div><div class="toc"><dl class="toc"><dt><span class="sect2"><a href="dict-int.html#id-1.11.7.20.4">F.11.1. Configuration</a></span></dt><dt><span class="sect2"><a href="dict-int.html#id-1.11.7.20.5">F.11.2. Usage</a></span></dt></dl></div><a id="id-1.11.7.20.2" class="indexterm"></a><p>
- <code class="filename">dict_int</code> is an example of an add-on dictionary template
- for full-text search. The motivation for this example dictionary is to
- control the indexing of integers (signed and unsigned), allowing such
- numbers to be indexed while preventing excessive growth in the number of
- unique words, which greatly affects the performance of searching.
- </p><div class="sect2" id="id-1.11.7.20.4"><div class="titlepage"><div><div><h3 class="title">F.11.1. Configuration</h3></div></div></div><p>
- The dictionary accepts two options:
- </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
- The <code class="literal">maxlen</code> parameter specifies the maximum number of
- digits allowed in an integer word. The default value is 6.
- </p></li><li class="listitem"><p>
- The <code class="literal">rejectlong</code> parameter specifies whether an overlength
- integer should be truncated or ignored. If <code class="literal">rejectlong</code> is
- <code class="literal">false</code> (the default), the dictionary returns the first
- <code class="literal">maxlen</code> digits of the integer. If <code class="literal">rejectlong</code> is
- <code class="literal">true</code>, the dictionary treats an overlength integer as a stop
- word, so that it will not be indexed. Note that this also means that
- such an integer cannot be searched for.
- </p></li></ul></div></div><div class="sect2" id="id-1.11.7.20.5"><div class="titlepage"><div><div><h3 class="title">F.11.2. Usage</h3></div></div></div><p>
- Installing the <code class="literal">dict_int</code> extension creates a text search
- template <code class="literal">intdict_template</code> and a dictionary <code class="literal">intdict</code>
- based on it, with the default parameters. You can alter the
- parameters, for example
-
- </p><pre class="programlisting">
- mydb# ALTER TEXT SEARCH DICTIONARY intdict (MAXLEN = 4, REJECTLONG = true);
- ALTER TEXT SEARCH DICTIONARY
- </pre><p>
-
- or create new dictionaries based on the template.
- </p><p>
- To test the dictionary, you can try
-
- </p><pre class="programlisting">
- mydb# select ts_lexize('intdict', '12345678');
- ts_lexize
- -----------
- {123456}
- </pre><p>
-
- but real-world usage will involve including it in a text search
- configuration as described in <a class="xref" href="textsearch.html" title="Chapter 12. Full Text Search">Chapter 12</a>.
- That might look like this:
-
- </p><pre class="programlisting">
- ALTER TEXT SEARCH CONFIGURATION english
- ALTER MAPPING FOR int, uint WITH intdict;
- </pre><p>
-
- </p></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="contrib-dblink-build-sql-update.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="dict-xsyn.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">dblink_build_sql_update </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> F.12. dict_xsyn</td></tr></table></div></body></html>
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