Re: Odd explain estimate - Mailing list pgsql-performance

From Jim C. Nasby
Subject Re: Odd explain estimate
Date
Msg-id 20030731225959.GH55392@nasby.net
Whole thread Raw
In response to Re: Odd explain estimate  (Andrew Sullivan <andrew@libertyrms.info>)
Responses Re: Odd explain estimate
List pgsql-performance
On Thu, Jul 31, 2003 at 04:59:21PM -0400, Andrew Sullivan wrote:
> On Thu, Jul 31, 2003 at 02:51:45PM -0500, Jim C. Nasby wrote:
> If you really needed to set enable_seqscan=false (did you really?
> Are you sure that's not the cheapest way?), you might want to
> investigate expainding the statistics on the indexed column,
> increasing the correlation through clustering, and other such tricks.

Well, if I don't do this it wants to seqscan a table that occupies 350k
pages, instead of pulling a couple thousand rows. I started running it
with the seqscan and it's already taken way longer than it does if I
disable seqscan.

I guess I'll try expanding the statistics.
--
Jim C. Nasby, Database Consultant                  jim@nasby.net
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