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@ -1,4 +1,4 @@ |
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<!-- $Header: /cvsroot/pgsql/doc/src/sgml/indices.sgml,v 1.32 2002/06/21 03:25:53 momjian Exp $ --> |
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<!-- $Header: /cvsroot/pgsql/doc/src/sgml/indices.sgml,v 1.33 2002/06/21 16:52:00 momjian Exp $ --> |
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<chapter id="indexes"> |
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<title id="indexes-title">Indexes</title> |
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@ -181,9 +181,10 @@ CREATE INDEX <replaceable>name</replaceable> ON <replaceable>table</replaceable> |
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</synopsis> |
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<note> |
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<para> |
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Testing has shown that hash indexes are slower than btree indexes, |
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and the size and build time for hash indexes is much worse. For |
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these reasons, hash index use is discouraged. |
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Testing has shown hash indexes to be similar or slower than btree |
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indexes, and the index size and build time for hash indexes is much |
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worse. Hash indexes also suffer poor performance under high |
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concurrency. For these reasons, hash index use is discouraged. |
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</para> |
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</note> |
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</para> |
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