From: hubert depesz lubaczewski <depesz@depesz.com>
To: Andrus <kobruleht2@hot.ee>
Cc: pgsql-performance@postgresql.org
Subject: Re: Increasing select max(datecol) from bilkaib where datecol<=date'2008-11-01' and (cr='00' or db='00') speed
Date: Wed, 12 Nov 2008 20:39:19 +0100
Message-ID: <20081112193918.GA7752@depesz.com> (raw)
In-Reply-To: <gff26k$2etc$1@news.hub.org>
References: <gff26k$2etc$1@news.hub.org>
On Wed, Nov 12, 2008 at 07:02:10PM +0200, Andrus wrote:
> explain analyze select max(kuupaev) from bilkaib where
> kuupaev<=date'2008-11-01' and (cr='00' or db='00')
do you always have this: "(cr='00' or db='00')"? or do the values (00)
change?
if they don't change, or *most* of the queries have "(cr='00' or
db='00')", than the biggest time difference you will get after creating
this index:
create index test on bilkaib (kuupaev) where cr='00' or db='00';
depesz
--
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To: pgsql-performance@postgresql.org
Cc: depesz@depesz.com, kobruleht2@hot.ee
Subject: Re: Increasing select max(datecol) from bilkaib where datecol<=date'2008-11-01' and (cr='00' or db='00') speed
In-Reply-To: <20081112193918.GA7752@depesz.com>
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