From: A. Kretschmer <andreas.kretschmer@schollglas.com>
To: pgsql-sql@postgresql.org
Subject: Re: slow query
Date: Thu, 5 Apr 2007 07:11:27 +0200
Message-ID: <20070405051127.GA24814@a-kretschmer.de> (raw)
In-Reply-To: <7539aebb0704042017l70d83d53u9c2e5105620a3fa7@mail.gmail.com>
References: <7539aebb0704042017l70d83d53u9c2e5105620a3fa7@mail.gmail.com>
am Wed, dem 04.04.2007, um 23:17:54 -0400 mailte Sumeet folgendes:
> sm=> explain analyze select * from ma limit 10;
> QUERY
> PLAN
> -------------------------------------------------------------------------------------------------------------------------------------
> Limit (cost=0.00..0.45 rows=10 width=76) (actual time=21985.292..22204.340
> rows=10 loops=1)
> -> Seq Scan on ma (cost=0.00..2181956.92 rows=48235392 width=76) (actual
> time=21985.285..22204.308 rows=10 loops=1)
> Total runtime: 22204.476 ms
> (3 rows)
which version?
I have 8.1 and on a table with 1.9 million records i got:
scholl=# explain analyse select * from bde_meldungen limit 10;
QUERY PLAN
----------------------------------------------------------------------------------------------------------------------------
Limit (cost=0.00..0.34 rows=10 width=157) (actual time=19.570..19.660 rows=10 loops=1)
-> Seq Scan on bde_meldungen (cost=0.00..65748.33 rows=1957933 width=157) (actual time=19.565..19.587 rows=10 loops=1)
Total runtime: 19.845 ms
(3 rows)
If I remember correctly, since 8.0 or 8.1 we have a massive improvement with
LIMIT.
Andreas
--
Andreas Kretschmer
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To: pgsql-sql@postgresql.org
Cc: andreas.kretschmer@schollglas.com
Subject: Re: slow query
In-Reply-To: <20070405051127.GA24814@a-kretschmer.de>
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