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Home -> Community -> Mailing Lists -> Oracle-L -> Re: Fav. Urban Legend...
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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Author of:
Practical Oracle 8i: Building Efficient Databases
-----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.
|
|
-- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Jonathan Lewis INET: jonathan_at_jlcomp.demon.co.uk Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).Received on Wed Mar 13 2002 - 17:08:55 CST
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