On 21 Apr 2007 01:19:30 -0700, Steven <songxin328@gmail.com> wrote:

>Yeah, actually, I mean the cost based optimization.
>I think in general they were based on System-R model in calculating
>the execuation cost.
>that is: Total cost = i/o cost + cpu cost
>
>but Is there anything different when to implement this formula?
>I read this article below
>Cost Control: Inside the Oracle Optimizer
>and I am looking for similar articles about other dbms...
>=========
>Anyway, 3x for your reply~

Don Tov wrote a book on sql tuning published by O'Reilly discussing
Oracle, DB2 and sqlserver.
Please do not top post.

--