index help [message #353047] |
Fri, 10 October 2008 14:11 |
imraan
Messages: 21 Registered: June 2008 Location: ayangudi
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Junior Member |
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hi;
what will happen internally when we rebuild the index;
why sometimes index is not used after creating or rebuild the index;
pls explain me
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Re: index help [message #353048 is a reply to message #353047] |
Fri, 10 October 2008 14:16 |
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Mahesh Rajendran
Messages: 10708 Registered: March 2002 Location: oracleDocoVille
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Senior Member Account Moderator |
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>>why sometimes index is not used after creating or rebuild the index;
* bad sql
* based on available stats, CBO might have decided not to use an index
* outdated statistics.
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