Oracle-L: FW: URGENT BITMAP MERGE NOT WORKING

From: <Paula_Stankus_at_doh.state.fl.us>
Date: Sat, 10 Aug 2002 09:38:25 -0800
Message-ID: <F001.004B1617.20020810093825@fatcity.com>

Okay,

Again concate. bitmap local prefix index = 9 secs. and I can't get CBO to use bitmap merge even with index_combine hint - so explain plan shows just using by default index with part. key in it (year) and response time is a little over 1 minute. I wish to try bitmap merge - how can I get the CBO to do it. It might be faster than the concat. bitmap index but I can't try it. Help.
I have been doing explain plans and it accesses usually only the bitmapped index that either was created first or has the same key as what I have part. view on - year. In any case perf. is in minutes versus seconds and the explain plan does not show an index combine occurring.

However, I still think the combined bitmapped index query would perform better and can't make CBO try this even with index_combine hint /*+ INDEX_COMBINE */ ..... regardless of optimizer setting.

I cannot make it do an index_combine. I have used explain plan set.... then I use the utlxpls.sql from $ORACLE_HOME/rdbms/admin to check my plan. The timing is the same and explain plan show I am just using the index on year.

What about the paramater bitmap_merge_... do I need to bump this up?

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INET: Paula_Stankus_at_doh.state.fl.us

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