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@ -1,4 +1,4 @@ |
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<!-- $PostgreSQL: pgsql/doc/src/sgml/maintenance.sgml,v 1.80 2007/09/14 02:43:18 momjian Exp $ --> |
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<!-- $PostgreSQL: pgsql/doc/src/sgml/maintenance.sgml,v 1.81 2007/09/14 13:43:03 momjian Exp $ --> |
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<chapter id="maintenance"> |
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<title>Routine Database Maintenance Tasks</title> |
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@ -262,12 +262,19 @@ |
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</tip> |
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<para> |
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Recommended practice for most sites is to schedule a database-wide |
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<command>ANALYZE</> once a day at a low-usage time of day; this can |
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usefully be combined with a nightly <command>VACUUM</>. However, |
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sites with relatively slowly changing table statistics might find that |
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this is overkill, and that less-frequent <command>ANALYZE</> runs |
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are sufficient. |
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Fortunately, autovacuum (<xref linkend="autovacuum">) monitors table |
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activity and performs <command>ANALYZE</command>s when necessary. This |
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eliminates the need for administrators to manually schedule |
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<command>ANALYZE</command>. |
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</para> |
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<para> |
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For those not using autovacuum, one approach is to schedule a |
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database-wide <command>ANALYZE</> once a day at a low-usage time of |
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day; this can usefully be combined with a nightly <command>VACUUM</>. |
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However, sites with relatively slowly changing table statistics might |
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find that this is overkill, and that less-frequent <command>ANALYZE</> |
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runs are sufficient. |
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</para> |
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</sect2> |
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