Re: Statistics and optimizer

Actually, a simple way of looking at it is that if *any* hint is used, other than "rule", then CBO will be used. If CBO is used for any part of the query, ie subqueries, then the entire statement will use CBO.

• ricky

Ann Myhre wrote:

> Does anyone know if optimizer will use the costbased method if no
> statistcis is gathered (ANALYZE TABLE etc.)? I have information saying
> that if no statistics is gathered, optimizer will choose the rulebased
> method, and another source saying that then will optimizer (if set to
> CHOOSE) choose some default values includes in Oracle. Help
> anyone? Ann
Received on Mon May 07 2001 - 19:47:54 CDT