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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>DISCARD</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="sql-delete.html" title="DELETE" /><link rel="next" href="sql-do.html" title="DO" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">DISCARD</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="sql-delete.html" title="DELETE">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="sql-commands.html" title="SQL Commands">Up</a></td><th width="60%" align="center">SQL Commands</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="sql-do.html" title="DO">Next</a></td></tr></table><hr /></div><div class="refentry" id="SQL-DISCARD"><div class="titlepage"></div><a id="id-1.9.3.101.1" class="indexterm"></a><div class="refnamediv"><h2><span class="refentrytitle">DISCARD</span></h2><p>DISCARD — discard session state</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><pre class="synopsis">
   3 DISCARD { ALL | PLANS | SEQUENCES | TEMPORARY | TEMP }
   4 </pre></div><div class="refsect1" id="id-1.9.3.101.5"><h2>Description</h2><p>
   5    <code class="command">DISCARD</code> releases internal resources associated with a
   6    database session.  This command is useful for partially or fully
   7    resetting the session's state.  There are several subcommands to
   8    release different types of resources; the <code class="command">DISCARD ALL</code>
   9    variant subsumes all the others, and also resets additional state.
  10   </p></div><div class="refsect1" id="id-1.9.3.101.6"><h2>Parameters</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><code class="literal">PLANS</code></span></dt><dd><p>
  11       Releases all cached query plans, forcing re-planning to occur
  12       the next time the associated prepared statement is used.
  13      </p></dd><dt><span class="term"><code class="literal">SEQUENCES</code></span></dt><dd><p>
  14       Discards all cached sequence-related state,
  15       including <code class="function">currval()</code>/<code class="function">lastval()</code>
  16       information and any preallocated sequence values that have not
  17       yet been returned by <code class="function">nextval()</code>.
  18       (See <a class="xref" href="sql-createsequence.html" title="CREATE SEQUENCE"><span class="refentrytitle">CREATE SEQUENCE</span></a> for a description of
  19       preallocated sequence values.)
  20      </p></dd><dt><span class="term"><code class="literal">TEMPORARY</code> or <code class="literal">TEMP</code></span></dt><dd><p>
  21       Drops all temporary tables created in the current session.
  22      </p></dd><dt><span class="term"><code class="literal">ALL</code></span></dt><dd><p>
  23       Releases all temporary resources associated with the current
  24       session and resets the session to its initial state.
  25       Currently, this has the same effect as executing the following sequence
  26       of statements:
  27 </p><pre class="programlisting">
  28 CLOSE ALL;
  29 SET SESSION AUTHORIZATION DEFAULT;
  30 RESET ALL;
  31 DEALLOCATE ALL;
  32 UNLISTEN *;
  33 SELECT pg_advisory_unlock_all();
  34 DISCARD PLANS;
  35 DISCARD TEMP;
  36 DISCARD SEQUENCES;
  37 </pre></dd></dl></div></div><div class="refsect1" id="id-1.9.3.101.7"><h2>Notes</h2><p>
  38     <code class="command">DISCARD ALL</code> cannot be executed inside a transaction block.
  39    </p></div><div class="refsect1" id="id-1.9.3.101.8"><h2>Compatibility</h2><p>
  40    <code class="command">DISCARD</code> is a <span class="productname">PostgreSQL</span> extension.
  41   </p></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="sql-delete.html" title="DELETE">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="sql-commands.html" title="SQL Commands">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="sql-do.html" title="DO">Next</a></td></tr><tr><td width="40%" align="left" valign="top">DELETE </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 18.0 Documentation">Home</a></td><td width="40%" align="right" valign="top"> DO</td></tr></table></div></body></html>