Cost based Optimizer

I am looking for suggestions and tips from Oracle experts who have used the COST based optimizer. We are facing some problems with it and have found that the RULE based optimizer is much more predictable and efficient for our environment. However, I heard that Oracle might discontinue RULE based optimizer. So at this point, I am looking for input from Oracle experts. I have analyzed all the tables and built the required indexes. The COST based optimizer doesn't seem to be smart enough to pick the correct indexes. Also, the execution time is much lower when I alter the session to use the RULE based optimizer. The execution plan clearly shows that the RULE based optimizer is using indexes and the COST based optimizer is doing a full table scan. Any ideas???

Murali

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Murali Kazhipurath
Technical Consultant
Kaustubam (Database and Internet Solutions Provider)
murali_at_jps.net
Phone # (916) 773 1918