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hasta_l3_at_hotmail.com wrote:
> Dear group,
>
> Our applications are supporting Oracle 8.1.7 and Oracle 9, for many
> customers with varying level of activity.
> We use the rule based optimizer to ensure the stability of the sql
> statement's execution plans.
>
> We are thinking of moving to the cost based optimizer, at least in
> Oracle 10.
>
> Would you have a strategy to recommand ?
Take Jonathan Lewis' three day Optimising Oracle workshop and buy his book on the CBO.
You can't use it well if you don't understand it.
> What is the first Oracle release with a cost based optimizer working
> reasonably well ?
8.1.7.4.
Well you did say "reasonably."
> How do you check the performances of your applications across oracle
> releases and customers with that optimizer ?
Write a decent SLA and see if you comply with it.
-- Daniel Morgan University of Washington Puget Sound Oracle Users GroupReceived on Sat Sep 23 2006 - 11:21:59 CDT