From: Dirk.Lutzebaeck@t-online.de
To: John A Meinel <john@arbash-meinel.com>
Cc: Greg Stark <gsstark@mit.edu>
Cc: pgsql-performance@postgresql.org
Cc: tgl@sss.pgh.pa.us
Subject: Re: query produces 1 GB temp file
Date: Sun, 06 Feb 2005 17:04:05 +0100
Message-ID: <42063FF5.9040707@aeccom.com> (raw)
In-Reply-To: <4206356C.9060308@arbash-meinel.com>
References: <20050205182117.0125074@mail2.aeccom.com>
<87y8e2kb8j.fsf@stark.xeocode.com>
<42061B35.6000306@aeccom.com>
<4206356C.9060308@arbash-meinel.com>
John,
I'm doing VACUUM ANALYZE once a night. Before the tests I did VACUUM and
then ANALYZE.
Dirk
John A Meinel wrote:
> Dirk Lutzebaeck wrote:
>
>> Greg,
>>
>> Thanks for your analysis. But I dont get any better after bumping
>> STATISTICS target from 10 to 200.
>> explain analyze shows that the optimizer is still way off estimating
>> the rows. Is this normal? It still produces a 1 GB temp file.
>> I simplified the query a bit, now only two tables are involved (bi,
>> df). I also vacuumed.
>
>
>
> Are you just doing VACUUM? Or are you doing VACUUM ANALYZE? You might
> also try VACUUM ANALYZE FULL (in the case that you have too many dead
> tuples in the table).
>
> VACUUM cleans up, but doesn't adjust any planner statistics without
> ANALYZE.
>
> John
> =:->
>
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-performance@postgresql.org
Cc: Dirk.Lutzebaeck@t-online.de, john@arbash-meinel.com, gsstark@mit.edu, tgl@sss.pgh.pa.us
Subject: Re: query produces 1 GB temp file
In-Reply-To: <42063FF5.9040707@aeccom.com>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox