From: Scott Marlowe <smarlowe@g2switchworks.com>
To: Sergei Shelukhin <realgeek@gmail.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: any way to get rid of Bitmap Heap Scan recheck?
Date: Wed, 20 Jun 2007 17:06:25 -0500
Message-ID: <4679A4E1.2060106@g2switchworks.com> (raw)
In-Reply-To: <1179570137.996544.101940@w5g2000hsg.googlegroups.com>
References: <1179380547.753418.193030@w5g2000hsg.googlegroups.com>
<1179570137.996544.101940@w5g2000hsg.googlegroups.com>
Sergei Shelukhin wrote:
> Hi.
> I have the following join condition in a query
> "posttag inner join tag ON posttag.tagid = tag.id and tag.name =
> 'blah'"
> tag.id is PK, I have indexes on posttag.tagid and tag.name both
> created with all the options set to default.
> PG version is 8.1.
>
>
> The query is very slow (3 minutes on test data), here's what takes all
> the time, from explain results:Any ideas?
Yes, post the output of
explain analyze select ... (rest of query here)
for starters
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To: pgsql-performance@postgresql.org
Cc: smarlowe@g2switchworks.com, realgeek@gmail.com
Subject: Re: any way to get rid of Bitmap Heap Scan recheck?
In-Reply-To: <4679A4E1.2060106@g2switchworks.com>
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