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<chapter id="maintenance">

<title>Routine Database Maintenance Tasks</title>

</tip>

<para>

Recommended practice for most sites is to schedule a database-wide

<command>ANALYZE</> once a day at a low-usage time of day; this can

usefully be combined with a nightly <command>VACUUM</>. However,

sites with relatively slowly changing table statistics might find that

this is overkill, and that less-frequent <command>ANALYZE</> runs

are sufficient.

Fortunately, autovacuum (<xref linkend="autovacuum">) monitors table

activity and performs <command>ANALYZE</command>s when necessary. This

eliminates the need for administrators to manually schedule

<command>ANALYZE</command>.

</para>

<para>

For those not using autovacuum, one approach is to schedule a

database-wide <command>ANALYZE</> once a day at a low-usage time of

day; this can usefully be combined with a nightly <command>VACUUM</>.

However, sites with relatively slowly changing table statistics might

find that this is overkill, and that less-frequent <command>ANALYZE</>

runs are sufficient.

</para>

</sect2>