From: sathiya psql <sathiya.psql@gmail.com>
To: A. Kretschmer <andreas.kretschmer@schollglas.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: count * performance issue
Date: Thu, 6 Mar 2008 12:36:48 +0530
Message-ID: <f966c2ee0803052306h5e5481bdk489b2c01d0ab930b@mail.gmail.com> (raw)
In-Reply-To: <20080306065750.GD21084@a-kretschmer.de>
References: <f966c2ee0803052142l6a105678jfe2da92a0d9371@mail.gmail.com>
<f966c2ee0803052143k4570d771o6c300647d3b987d@mail.gmail.com>
<20080306060829.GA21084@a-kretschmer.de>
<bf54be870803052215y5bb56235k5ea05ada1d701022@mail.gmail.com>
<47CF8EA6.8070503@mark.mielke.cc>
<20080306063643.GB21084@a-kretschmer.de>
<f966c2ee0803052247n783dae24i9058d148bd17385e@mail.gmail.com>
<20080306065750.GD21084@a-kretschmer.de>
QUERY PLAN
------------------------------------------------------------------------------------------------------------------------------
Aggregate (cost=205756.95..205756.95 rows=1 width=0) (actual time=
114675.042..114675.042 rows=1 loops=1)
-> Seq Scan on call_log (cost=0.00..193224.16 rows=5013112 width=0)
(actual time=11.754..91429.594 rows=5061619 loops=1)
Filter: (call_id > 0)
Total runtime: 114699.797 ms
(4 rows)
it is now taking 114 seconds, i think because of load in my system.... any
way will you explain., what is this COST, actual time and other stuffs....
On Thu, Mar 6, 2008 at 12:27 PM, A. Kretschmer <
andreas.kretschmer@schollglas.com> wrote:
> am Thu, dem 06.03.2008, um 12:17:55 +0530 mailte sathiya psql folgendes:
> > TRIGGER i can use if i want the count of the whole table, but i require
> for
> > some of the rows with WHERE condition....
> >
> > so how to do that ???
>
> Okay, in this case a TRIGGER are a bad idea. You can use an INDEX on
> this row. Can you show us the output for a EXPLAIN ANALYSE SELECT
> count(*) from <your_table> WHERE <your_row> = ... ?
>
>
> Andreas
> --
> Andreas Kretschmer
> Kontakt: Heynitz: 035242/47150, D1: 0160/7141639 (mehr: -> Header)
> GnuPG-ID: 0x3FFF606C, privat 0x7F4584DA http://wwwkeys.de.pgp.net
>
> --
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To: pgsql-performance@postgresql.org
Cc: sathiya.psql@gmail.com, andreas.kretschmer@schollglas.com
Subject: Re: count * performance issue
In-Reply-To: <f966c2ee0803052306h5e5481bdk489b2c01d0ab930b@mail.gmail.com>
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