Re: 4 way JOIN using aliases

From: "Dave Held" <dave(dot)held(at)arrayservicesgrp(dot)com>
To: "PostgreSQL Perform" <pgsql-performance(at)postgresql(dot)org>
Subject: Re: 4 way JOIN using aliases
Date: 2005-04-12 18:22:12
Message-ID: 49E94D0CFCD4DB43AFBA928DDD20C8F9026184AD@asg002.asg.local
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> -----Original Message-----
> From: Keith Worthington [mailto:keithw(at)narrowpathinc(dot)com]
> Sent: Tuesday, April 12, 2005 1:14 PM
> To: Dave Held; PostgreSQL Perform
> Subject: Re: [PERFORM] 4 way JOIN using aliases
>
> > > I run vacuumdb with the analyze option every morning via a
> > > cron job. In my ignorance I do not know if that is the same
> > > thing.
> >
> > Pass it an --analyze option if you aren't already.
>
> Here is the command I have in the cron file.
>
> vacuumdb --full --analyze --verbose --username dbuser
> --dbname ${IPA_DB} >>
> ${IPA_LOG_DIR}/ipavcmdb.log 2>&1
>
> If this performs the analyze as I thought it should I do not
> know why the row
> count is so badly off.

You may need to increase the statistics target for the relevant
columns. Look at:

http://www.postgresql.org/docs/7.4/static/sql-altertable.html

In particular, the SET STATISTICS clause.

__
David B. Held
Software Engineer/Array Services Group
200 14th Ave. East, Sartell, MN 56377
320.534.3637 320.253.7800 800.752.8129

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