Re: any way to get rid of Bitmap Heap Scan recheck?

From: Scott Marlowe <smarlowe(at)g2switchworks(dot)com>
To: Sergei Shelukhin <realgeek(at)gmail(dot)com>
Cc: pgsql-performance(at)postgresql(dot)org
Subject: Re: any way to get rid of Bitmap Heap Scan recheck?
Date: 2007-06-20 22:06:25
Message-ID: 4679A4E1.2060106@g2switchworks.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-performance

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

In response to

Browse pgsql-performance by date

  From Date Subject
Next Message Scott Marlowe 2007-06-20 22:13:15 Re: [GENERAL] [PERFORM] Postgres VS Oracle
Previous Message Andrew Sullivan 2007-06-20 21:40:24 Re: Performance query about large tables, lots of concurrent access