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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <HTML ><HEAD ><TITLE >CHECKPOINT</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 9.2.24 Documentation" HREF="index.html"><LINK REL="UP" TITLE="SQL Commands" HREF="sql-commands.html"><LINK REL="PREVIOUS" TITLE="BEGIN" HREF="sql-begin.html"><LINK REL="NEXT" TITLE="CLOSE" HREF="sql-close.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="2017-11-06T22:43:11"></HEAD ><BODY CLASS="REFENTRY" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="5" ALIGN="center" VALIGN="bottom" ><A HREF="index.html" >PostgreSQL 9.2.24 Documentation</A ></TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="top" ><A TITLE="BEGIN" HREF="sql-begin.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="CLOSE" HREF="sql-close.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><H1 ><A NAME="SQL-CHECKPOINT" ></A >CHECKPOINT</H1 ><DIV CLASS="REFNAMEDIV" ><A NAME="AEN66448" ></A ><H2 >Name</H2 >CHECKPOINT -- force a transaction log checkpoint</DIV ><DIV CLASS="REFSYNOPSISDIV" ><A NAME="AEN66453" ></A ><H2 >Synopsis</H2 ><PRE CLASS="SYNOPSIS" >CHECKPOINT</PRE ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN66455" ></A ><H2 >Description</H2 ><P > A checkpoint is a point in the transaction log sequence at which all data files have been updated to reflect the information in the log. All data files will be flushed to disk. Refer to <A HREF="wal-configuration.html" >Section 29.4</A > for more details about what happens during a checkpoint. </P ><P > The <TT CLASS="COMMAND" >CHECKPOINT</TT > command forces an immediate checkpoint when the command is issued, without waiting for a regular checkpoint scheduled by the system (controlled by the settings in <A HREF="runtime-config-wal.html#RUNTIME-CONFIG-WAL-CHECKPOINTS" >Section 18.5.2</A >). <TT CLASS="COMMAND" >CHECKPOINT</TT > is not intended for use during normal operation. </P ><P > If executed during recovery, the <TT CLASS="COMMAND" >CHECKPOINT</TT > command will force a restartpoint (see <A HREF="wal-configuration.html" >Section 29.4</A >) rather than writing a new checkpoint. </P ><P > Only superusers can call <TT CLASS="COMMAND" >CHECKPOINT</TT >. </P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN66468" ></A ><H2 >Compatibility</H2 ><P > The <TT CLASS="COMMAND" >CHECKPOINT</TT > command is a <SPAN CLASS="PRODUCTNAME" >PostgreSQL</SPAN > language 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-begin.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-close.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >BEGIN</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" >CLOSE</TD ></TR ></TABLE ></DIV ></BODY ></HTML >