From: Steinar H. Gunderson <sgunderson@bigfoot.com>
To: Peter Eisentraut <peter_e@gmx.net>
Cc: pgsql-performance@postgresql.org
Subject: Re: Index scan startup time
Date: Thu, 30 Mar 2006 14:02:06 +0200
Message-ID: <20060330120206.GA13075@uio.no> (raw)
In-Reply-To: <200603301359.11038.peter_e@gmx.net>
References: <200603301359.11038.peter_e@gmx.net>
On Thu, Mar 30, 2006 at 01:59:10PM +0200, Peter Eisentraut wrote:
> EXPLAIN ANALYZE select activity_id from activity where state in (10000, 10001)
> order by activity_id limit 100;
>
> QUERY PLAN
>
> Limit (cost=0.00..622.72 rows=100 width=8) (actual
> time=207356.054..207356.876 rows=100 loops=1)
> -> Index Scan using activity_pk on activity (cost=0.00..40717259.91
> rows=6538650 width=8) (actual time=207356.050..207356.722 rows=100 loops=1)
> Filter: ((state = 10000) OR (state = 10001))
> Total runtime: 207357.000 ms
>
> The table has seen VACUUM FULL and REINDEX before this.
The index scan is by activity_id, not by state. Do you have an index on state
at all?
/* Steinar */
--
Homepage: http://www.sesse.net/
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To: pgsql-performance@postgresql.org
Cc: sgunderson@bigfoot.com, peter_e@gmx.net
Subject: Re: Index scan startup time
In-Reply-To: <20060330120206.GA13075@uio.no>
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