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Date: Fri, 22 Jun 2012 11:04:36 -0700
From: David Kerr <dmk@mr-paradox.net>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: pgsql-performance@postgresql.org
Subject: Re: Drop statistics?
Message-ID: <20120622180436.GB94572@mr-paradox.net>
References: <20120622170755.GB93663@mr-paradox.net>
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On Fri, Jun 22, 2012 at 01:27:51PM -0400, Tom Lane wrote:
- David Kerr <dmk@mr-paradox.net> writes:
- > I'm trying to work through a root cause on a performance problem. I'd like to
- > be able to "show" that a problem was fixed by analyzing the table.
- 
- > what i've done is
- > set default_statistics_target=1
- > analyze <Table>
- 
- > That gets rid of most of the rows in pg_stats, but i'm still getting decent performance.
- 
- I usually do something like
- 
- DELETE FROM pg_statistic WHERE starelid = 'foo'::regclass;
- 
- (you need to be superuser to be allowed to do this).
- 
- You may need to keep an eye on whether auto-analyze is coming along and
- undoing what you did, too.
- 
- 			regards, tom lane
- 

Awesome, thanks!

Dave