Re: query plan worse after analyze

On Sat, 6 Oct 2007, Tom Lane wrote:

> "Jeff Frost" <jeff@frostconsultingllc.com> writes:
>> Before analyze it seems to choose Bitmap Heap Scan on episodes
>> current_episode, but after it chooses Index Scan Backward using
>> index_episodes_on_publish_on on episodes current_episode.
>
> Have you tried raising the stats target for "episodes"?  Seems like
> the problem is a misestimate of the frequency of matches for
> season_id = something.

Can you set the stats target for an entire table up?

I tried this:

ALTER TABLE episodes ALTER COLUMN season_id SET STATISTICS 1000;

and got the same plan.

And since I had this on a test server, I set the default stats target
up to 100, reran analyze and got the same plan.

Same if I up it to 1000. :-(

--
Jeff Frost, Owner     <jeff@frostconsultingllc.com>
Frost Consulting, LLC     http://www.frostconsultingllc.com/
Phone: 650-780-7908    FAX: 650-649-1954