RE: dba_tables.num_rows is less than dba_indexes.num_rows

From: Lex de Haan <lex.de.haan_at_naturaljoin.nl>
Date: Tue, 9 Aug 2005 09:14:32 +0200
Message-Id: <20050809071437.694E91DCE9C@turing.freelists.org>

indexes are typically used for single entry searches, or range scans -- in which case the total number of entries is irrelevant for the CBO. and even with an index full scan, the index *size* is more important than the number of entries...

kind regards,

Lex.  

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-----Original Message-----

So does it matter that the indexes' num_rows are bigger than that of the table? I'm concerned that some indexes will never be used as the CBO will think it's bigger than the table or some of the other indexes.

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http://www.freelists.org/webpage/oracle-l Received on Tue Aug 09 2005 - 02:16:39 CDT