This question is just way too broad and too generic,and lacks any
information about version of Oracle, and which optimizer is being used,
to be answered properly.
If your version of Oracle (or usage of optimizer) doesn't support the
IN-list iterator (ie transforms your OR in an IN) *AND* the where
clause forces to optimizer to conduct full table scans, AND you don't
use bind variables, then that would be sufficient to bring any system
on its knees.
For the time being, I guess the best advice you hire someone to tune
your sql-statements for you. This is not the place for broad
discussions on vague requests calling in for crystal balls. They have
been sold out a long time ago, even in the Netherlands, and my crystal
ball has worn out.
--
Sybrand Bakker
Senior Oracle DBA
Received on Thu Aug 18 2005 - 08:11:44 CDT
