Re: cross table indexes or something? - Mailing list pgsql-performance

From Jeremiah Jahn
Subject Re: cross table indexes or something?
Date
Msg-id 1070392092.22346.43.camel@bluejay.goodinassociates.com
Whole thread Raw
In response to Re: cross table indexes or something?  (Josh Berkus <josh@agliodbs.com>)
Responses Re: cross table indexes or something?
List pgsql-performance
Thanks to all, I had already run analyze.  But the STATISTICS setting
seems to have worked. I'm just not sure what it did..? Would anyone care
to explain.


On Mon, 2003-12-01 at 13:47, Josh Berkus wrote:
> Jeremiah,
>
> > I've attached the Analyze below. I have no idea why the db thinks there
> > is only 1 judge named simth. Is there some what I can inform the DB
> > about this. In actuality, there aren't any judges named smith at the
> > moment, but there are 22K people named smith.
>
> No, Hannu meant that you may need to run the following command:
>
> ANALYZE actor;
>
> ... to update the database statistics on the actors table.   That is a
> maintainence task that needs to be run periodically.
>
> If that doesn't fix the bad plan, then the granularity of statistics on the
> full_name column needs updating; I suggest:
>
> ALTER TABLE actor ALTER COLUMN full_name SET STATISTICS 100;
> ANALYZE actor;
>
> And if it's still choosing  a slow nested loop, up the stats to 250.
--
Jeremiah Jahn <jeremiah@cs.earlham.edu>


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