Re: Rule Based Optimization Going Away?

"Peter Kellner" <pkellner_at_seventythirdstreet.com> wrote in message news:ccec98ba.0210021655.32903b35_at_posting.google.com...
> I just was told by an Oracle Consultant that Oracle is planning on
> obsoleting rule based optimization and that in the future sometime,
> everyone will have to use cost based. Could this be true?

Yup. There's a public document admitting as much on Metalink.

>I have
> always used rule based when I know the distribution of the data pretty
> well ahead of time and can be smarter than the cost optimizer.
>

Then you need to get with the rhythm and realise that the Opimizer has got a whole lot more smarter than you're giving it credit for. So when was the last time you could predict, with the rule based optimizer, what would be in Index leaf nodes before you actually got to read them??? Huh??

Seriously: there is no way you can beat the optimizer these days. And if you say you can, I don't believe you.

Anyway, whether I believe you or not: by 10i, the rule-based optimizer is finished. So even if you are the God's gift to predicting access paths, tough luck: Oracle won't support you.

> Any official Oracle Info on this would be appreciated.
>

You don't need any more "official" info than is readily available from Metalink. The Rule Based Optimizer is DEAD and you need to upgrade. It's not a particular pain: the CBO is good these days. But you need to stop wearing the flared jeans and oversized-lapels, and get with the groove. Man.

Regards
HJR
> -Peter Kellner
Received on Wed Oct 02 2002 - 20:30:28 CDT