RE: dba_tables.num_rows is less than dba_indexes.num_rows
- From: "Lex de Haan" <lex.de.haan@xxxxxxxxxxxxxx>
- To: <Leng.Kaing@xxxxxxxxxxx>, "'Wolfgang Breitling'" <breitliw@xxxxxxxxxxxxx>
- Date: Tue, 9 Aug 2005 09:14:32 +0200
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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