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<refentry id="sql-checkpoint">

<docinfo>

<date>2001-01-13</date>

<date>2001-01-24</date>

</docinfo>

<refmeta>

<refnamediv>

<refname>CHECKPOINT</refname>

<refpurpose>Force transaction logto disk</refpurpose>

<refpurpose>Force transaction logcheckpoint</refpurpose>

</refnamediv>

<refsynopsisdiv>

<title>Description</title>

<para>

This documentation needs to be written.

Write-Ahead Logging (WAL) puts a checkpoint in the transaction log

every 300 seconds by default. (This may be changed by the run-time

configuration option <parameter>CHECKPOINT_TIMEOUT</parameter>.)

The <command>CHECKPOINT</command> command forces a checkpoint at

the point at which the command is issued. The next automatic

checkpoint will still happen after the original cycle expires.

</para>

<para>

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 the

<citetitle>PostgreSQL Administrator's Guide</citetitle> for more

information about the WAL system.

</para>

</refsect1>