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@ -1,5 +1,5 @@ |
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<!-- |
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$PostgreSQL: pgsql/doc/src/sgml/maintenance.sgml,v 1.51.2.1 2005/12/07 05:36:08 momjian Exp $ |
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$PostgreSQL: pgsql/doc/src/sgml/maintenance.sgml,v 1.51.2.2 2005/12/07 14:36:08 momjian Exp $ |
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--> |
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<chapter id="maintenance"> |
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@ -142,8 +142,8 @@ $PostgreSQL: pgsql/doc/src/sgml/maintenance.sgml,v 1.51.2.1 2005/12/07 05:36:08 |
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just <command>VACUUM</command>, marks expired data in tables and |
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indexes for future reuse; it does <emphasis>not</emphasis> attempt |
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to reclaim the space used by this expired data unless the space is |
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at the end of the table and an exclusive lock can be obtained easily |
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on the table. Unused space at the start or middle of the file does |
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at the end of the table and an exclusive table lock can be easily |
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obtained. Unused space at the start or middle of the file does |
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not result in the file being shortened and space returned to the |
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operating system. This variant of <command>VACUUM</command> can be |
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run concurrently with normal database operations. |
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