Re: CBO picks wrong plan after analyze. FIRST_ROWS hint is workaround. ALL_ROWS causes wrong plan

Sybrand Bakker wrote:
> On 21 Sep 2006 10:58:34 -0700, oracle10_at_gmail.com wrote:
>
> >Are there cases when following Oracle Recommendation by frequent
> >ANALYZE/stats gathering causes CBO to go astray?
>
> Yes. That is one of the reasons why you should dbms_stats instead of
> ANALYZE. Dbms_stats can save the old 'good' statistics to a stats
> table, so you can easily restore them.
> Also many people warn against frequent analysis.
> IMO, I think frequent analysis, without saving the old statistics
> (which seems to be the norm in my office) is just asking for trouble.
>
> --
> Sybrand Bakker, Senior Oracle DBA

Thanks for advise against frequent analysis. I heard that CBO in 8i was inferior to RBO. Is that your experience? Thanks Received on Fri Sep 22 2006 - 13:15:45 CDT