Re: Index access much slower than expected.

Can you post the original plan?
 
David Fitzjarrell





________________________________
From: Kenneth Naim <kennethnaim_at_gmail.com>
To: oracle-l_at_freelists.org
Sent: Thu, May 19, 2011 9:28:26 AM
Subject: Index access much slower than expected.


I have an application generated 4 table query that produced explain plan that 
has an index join of 3 indexes (hash join of 2 indexes hash joined to a third) 
among the other joins. The 3 indexes are on the same table mdp, it has 55k rows 
and is 88mb in size, 309 columns, 1200 chained rows.
The query ran for 9+ minutes with the index joins. With a full hint it runs 
1:40. I altered the session to disable index joins using the underscore 
parameter and got an identical plan to the original with just one of the 
indexes. I expected this to be perform better than the full scan as the 
predicate returns 2305 rows out of the 55k or 4% however it ran for over 10 
minutes. Any ideas on what I should be looking at to figure out why this is 
happening?
 
Thanks,
Ken 
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