From: | Jeremiah Jahn <jeremiah(at)cs(dot)earlham(dot)edu> |
---|---|
To: | postgres performance <pgsql-performance(at)postgresql(dot)org> |
Subject: | Re: cross table indexes or something? |
Date: | 2003-12-02 19:08:13 |
Message-ID: | 1070392092.22346.43.camel@bluejay.goodinassociates.com |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | 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(at)cs(dot)earlham(dot)edu>
From | Date | Subject | |
---|---|---|---|
Next Message | Jared Carr | 2003-12-02 19:14:19 | Re: A question on the query planner |
Previous Message | Greg Stark | 2003-12-02 18:59:56 | Re: A question on the query planner |