<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <HTML ><HEAD ><TITLE >DISCARD</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.79"><LINK REV="MADE" HREF="mailto:pgsql-docs@postgresql.org"><LINK REL="HOME" TITLE="PostgreSQL 9.6.21 Documentation" HREF="index.html"><LINK REL="UP" TITLE="SQL Commands" HREF="sql-commands.html"><LINK REL="PREVIOUS" TITLE="DELETE" HREF="sql-delete.html"><LINK REL="NEXT" TITLE="DO" HREF="sql-do.html"><LINK REL="STYLESHEET" TYPE="text/css" HREF="stylesheet.css"><META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=ISO-8859-1"><META NAME="creation" CONTENT="2021-02-27T18:26:08"></HEAD ><BODY CLASS="REFENTRY" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="4" ALIGN="center" VALIGN="bottom" ><A HREF="index.html" >PostgreSQL 9.6.21 Documentation</A ></TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="top" ><A TITLE="DELETE" HREF="sql-delete.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="10%" ALIGN="left" VALIGN="top" ><A HREF="sql-commands.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="60%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="20%" ALIGN="right" VALIGN="top" ><A TITLE="DO" HREF="sql-do.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><H1 ><A NAME="SQL-DISCARD" ></A >DISCARD</H1 ><DIV CLASS="REFNAMEDIV" ><A NAME="AEN85877" ></A ><H2 >Name</H2 >DISCARD -- discard session state</DIV ><DIV CLASS="REFSYNOPSISDIV" ><A NAME="AEN85880" ></A ><H2 >Synopsis</H2 ><PRE CLASS="SYNOPSIS" >DISCARD { ALL | PLANS | SEQUENCES | TEMPORARY | TEMP }</PRE ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN85882" ></A ><H2 >Description</H2 ><P > <TT CLASS="COMMAND" >DISCARD</TT > releases internal resources associated with a database session. This command is useful for partially or fully resetting the session's state. There are several subcommands to release different types of resources; the <TT CLASS="COMMAND" >DISCARD ALL</TT > variant subsumes all the others, and also resets additional state. </P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN85887" ></A ><H2 >Parameters</H2 ><P ></P ><DIV CLASS="VARIABLELIST" ><DL ><DT ><TT CLASS="LITERAL" >PLANS</TT ></DT ><DD ><P > Releases all cached query plans, forcing re-planning to occur the next time the associated prepared statement is used. </P ></DD ><DT ><TT CLASS="LITERAL" >SEQUENCES</TT ></DT ><DD ><P > Discards all cached sequence-related state, including <CODE CLASS="FUNCTION" >currval()</CODE >/<CODE CLASS="FUNCTION" >lastval()</CODE > information and any preallocated sequence values that have not yet been returned by <CODE CLASS="FUNCTION" >nextval()</CODE >. (See <A HREF="sql-createsequence.html" >CREATE SEQUENCE</A > for a description of preallocated sequence values.) </P ></DD ><DT ><TT CLASS="LITERAL" >TEMPORARY</TT > or <TT CLASS="LITERAL" >TEMP</TT ></DT ><DD ><P > Drops all temporary tables created in the current session. </P ></DD ><DT ><TT CLASS="LITERAL" >ALL</TT ></DT ><DD ><P > Releases all temporary resources associated with the current session and resets the session to its initial state. Currently, this has the same effect as executing the following sequence of statements: </P><PRE CLASS="PROGRAMLISTING" >SET SESSION AUTHORIZATION DEFAULT; RESET ALL; DEALLOCATE ALL; CLOSE ALL; UNLISTEN *; SELECT pg_advisory_unlock_all(); DISCARD PLANS; DISCARD SEQUENCES; DISCARD TEMP;</PRE ><P></P ></DD ></DL ></DIV ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN85916" ></A ><H2 >Notes</H2 ><P > <TT CLASS="COMMAND" >DISCARD ALL</TT > cannot be executed inside a transaction block. </P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN85920" ></A ><H2 >Compatibility</H2 ><P > <TT CLASS="COMMAND" >DISCARD</TT > is a <SPAN CLASS="PRODUCTNAME" >PostgreSQL</SPAN > extension. </P ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="sql-delete.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" ACCESSKEY="H" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="sql-do.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >DELETE</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="sql-commands.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >DO</TD ></TR ></TABLE ></DIV ></BODY ></HTML >