Which version of Oracle ?
Are you talking about 8.1 and
bitmapped star transformation,
or 8.0 and concatenated b-tree
indexing ?
--
Jonathan Lewis
Yet another Oracle-related web site: http://www.jlcomp.demon.co.uk
reash_at_attglobal.net wrote in message <39579D6A.69B88B94_at_attglobal.net>...
>We are having Oracle performance problems with a star schema.
>
>We have a 16 million row fact table surrounded by a dozen small
>dimension tables. If we run a report query joining the fact table with
>several dimension tables that only restricts on the dimension tables, it
>looks like Oracle is trying to do multiple scans of the fact table. If
>we place the restriction on the fact table, then explain plan seems to
>do something reasonable. In one case, the select ran 25 times faster if
>the restriction was placed on the fact table.
>
>Is this normal? Is there something I should know about Oracle and Star
>Schemas?
>
>Thanks
>Randy Eash
>
Received on Mon Jun 26 2000 - 00:00:00 CDT
