Ühel kenal päeval, E, 2006-08-14 kell 18:21, kirjutas Peter Eisentraut:
> Perez wrote:
> > I thought, from watching the list for a while, that the planner
> > statistics needed were known but that how to gather the statistics
> > was not?
>
> I think over the course of the discussion we have figured out that we
> would like to have cross-column correlation statistics. The precise
> mathematical incarnation hasn't been determined yet, as far as I can
> see. Collecting the statistics thereafter isn't that hard, but there
> needs to be a way to not collect an exponential volume of statistics on
> all column combinations.
I understood that the proposal was to collect only the stats where
needed (determined by user/dba) and use some rule-of-thumb values if no
collected stats were available.
--
----------------
Hannu Krosing
Database Architect
Skype Technologies OÜ
Akadeemia tee 21 F, Tallinn, 12618, Estonia
Skype me: callto:hkrosing
Get Skype for free: http://www.skype.com