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Re: Fav. Urban Legend...

From: Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk>
Date: Wed, 13 Mar 2002 15:08:55 -0800
Message-ID: <F001.00428666.20020313150855@fatcity.com>

Never true.

I think the reason it sprang into existence was that on the AND-EQUAL path, which combines single-column indexes to access a single table, the maximum number of indexes that can be combined is five.

Jonathan Lewis
http://www.jlcomp.demon.co.uk

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-----Original Message-----
To: Multiple recipients of list ORACLE-L <ORACLE-L_at_fatcity.com> Date: 13 March 2002 21:22

|> My next to favourite legends.
|> Oracle can only use 5 indexes in a query
|
|Was this ever true, on v6 or v7?
|
|I was told by Oracle support about six years ago about the 5 index
max. It
|seemed to work for me. On a six table query, with five indexes used,
when I
|disabled one index Oracle started using another and this helped
performance.
|So it seemed like the max of 5 was true.
|
|

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Author: Jonathan Lewis
  INET: jonathan_at_jlcomp.demon.co.uk

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Received on Wed Mar 13 2002 - 17:08:55 CST

Original text of this message

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