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+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<!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>7.6. LIMIT and OFFSET</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="queries-order.html" title="7.5. Sorting Rows (ORDER BY)" /><link rel="next" href="queries-values.html" title="7.7. VALUES Lists" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">7.6. <code class="literal">LIMIT</code> and <code class="literal">OFFSET</code></th></tr><tr><td width="10%" align="left"><a accesskey="p" href="queries-order.html" title="7.5. Sorting Rows (ORDER BY)">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="queries.html" title="Chapter 7. Queries">Up</a></td><th width="60%" align="center">Chapter 7. Queries</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 15.5 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="queries-values.html" title="7.7. VALUES Lists">Next</a></td></tr></table><hr /></div><div class="sect1" id="QUERIES-LIMIT"><div class="titlepage"><div><div><h2 class="title" style="clear: both">7.6. <code class="literal">LIMIT</code> and <code class="literal">OFFSET</code></h2></div></div></div><a id="id-1.5.6.10.2" class="indexterm"></a><a id="id-1.5.6.10.3" class="indexterm"></a><p>
+ <code class="literal">LIMIT</code> and <code class="literal">OFFSET</code> allow you to retrieve just
+ a portion of the rows that are generated by the rest of the query:
+</p><pre class="synopsis">
+SELECT <em class="replaceable"><code>select_list</code></em>
+ FROM <em class="replaceable"><code>table_expression</code></em>
+ [<span class="optional"> ORDER BY ... </span>]
+ [<span class="optional"> LIMIT { <em class="replaceable"><code>number</code></em> | ALL } </span>] [<span class="optional"> OFFSET <em class="replaceable"><code>number</code></em> </span>]
+</pre><p>
+ </p><p>
+ If a limit count is given, no more than that many rows will be
+ returned (but possibly fewer, if the query itself yields fewer rows).
+ <code class="literal">LIMIT ALL</code> is the same as omitting the <code class="literal">LIMIT</code>
+ clause, as is <code class="literal">LIMIT</code> with a NULL argument.
+ </p><p>
+ <code class="literal">OFFSET</code> says to skip that many rows before beginning to
+ return rows. <code class="literal">OFFSET 0</code> is the same as omitting the
+ <code class="literal">OFFSET</code> clause, as is <code class="literal">OFFSET</code> with a NULL argument.
+ </p><p>
+ If both <code class="literal">OFFSET</code>
+ and <code class="literal">LIMIT</code> appear, then <code class="literal">OFFSET</code> rows are
+ skipped before starting to count the <code class="literal">LIMIT</code> rows that
+ are returned.
+ </p><p>
+ When using <code class="literal">LIMIT</code>, it is important to use an
+ <code class="literal">ORDER BY</code> clause that constrains the result rows into a
+ unique order. Otherwise you will get an unpredictable subset of
+ the query's rows. You might be asking for the tenth through
+ twentieth rows, but tenth through twentieth in what ordering? The
+ ordering is unknown, unless you specified <code class="literal">ORDER BY</code>.
+ </p><p>
+ The query optimizer takes <code class="literal">LIMIT</code> into account when
+ generating query plans, so you are very likely to get different
+ plans (yielding different row orders) depending on what you give
+ for <code class="literal">LIMIT</code> and <code class="literal">OFFSET</code>. Thus, using
+ different <code class="literal">LIMIT</code>/<code class="literal">OFFSET</code> values to select
+ different subsets of a query result <span class="emphasis"><em>will give
+ inconsistent results</em></span> unless you enforce a predictable
+ result ordering with <code class="literal">ORDER BY</code>. This is not a bug; it
+ is an inherent consequence of the fact that SQL does not promise to
+ deliver the results of a query in any particular order unless
+ <code class="literal">ORDER BY</code> is used to constrain the order.
+ </p><p>
+ The rows skipped by an <code class="literal">OFFSET</code> clause still have to be
+ computed inside the server; therefore a large <code class="literal">OFFSET</code>
+ might be inefficient.
+ </p></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="queries-order.html" title="7.5. Sorting Rows (ORDER BY)">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="queries.html" title="Chapter 7. Queries">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="queries-values.html" title="7.7. VALUES Lists">Next</a></td></tr><tr><td width="40%" align="left" valign="top">7.5. Sorting Rows (<code class="literal">ORDER BY</code>) </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 15.5 Documentation">Home</a></td><td width="40%" align="right" valign="top"> 7.7. <code class="literal">VALUES</code> Lists</td></tr></table></div></body></html> \ No newline at end of file