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Hi,
Has anyone come across this before and is it a known problem or a
configuration issue ? We are running a datamart on 8.1.6 on AIX. All our
fact tables have a composite primary key and bitmap indexes on the indidual
columns of the primary keys. Statistics are adequate and up-to-date.
A lot of our queries are however defaulting to a full table scan which is
leading to long query times.
An example of of timings would be
A - Run query with no hints
Time to run - 6 mins + Cost - 13736 B - Run query forcing it to use composite index. Time to run - 1 min + Cost - 35558 C - Run query forcing it to use bitmap indexes. Time to run - 10 secs Cost - 15478
Any views or insights to this would be welcome. Thanks
Steve Received on Tue Apr 03 2001 - 10:40:52 CDT