From: Tino Wildenhain <tino@wildenhain.de>
To: Mark Cotner <mcotner@yahoo.com>
Cc: Gavin Sherry <swm@alcove.com.au>
Cc: Dan Harris <fbsd@drivefaster.net>
Cc: pgsql-performance@postgresql.org
Subject: Re: Speedier count(*)
Date: Thu, 11 Aug 2005 09:24:08 +0200
Message-ID: <1123745049.27613.1.camel@Andrea.peacock.de> (raw)
In-Reply-To: <BF204EF7.D9F6%mcotner@yahoo.com>
References: <BF204EF7.D9F6%mcotner@yahoo.com>
Am Donnerstag, den 11.08.2005, 00:40 -0400 schrieb Mark Cotner:
> Here's a trigger I wrote to perform essentially the same purpose. The nice
> thing about this is it keeps the number up to date for you, but you do incur
> slight overhead.
...
>
> CREATE TRIGGER del_rowcount_tr BEFORE DELETE ON test FOR EACH ROW EXECUTE
> PROCEDURE del_rowcount();
> CREATE TRIGGER add_rowcount_tr BEFORE INSERT ON test FOR EACH ROW EXECUTE
> PROCEDURE add_rowcount();
>
> INSERT INTO rowcount (tablename) VALUES ('test');
...
beware of problems with concurrency and even what happens
if transactions roll back. Maybe you can "fix" it a bit
by regulary correcting the count via cronjob or so.
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To: pgsql-performance@postgresql.org
Cc: tino@wildenhain.de, mcotner@yahoo.com, swm@alcove.com.au, fbsd@drivefaster.net
Subject: Re: Speedier count(*)
In-Reply-To: <1123745049.27613.1.camel@Andrea.peacock.de>
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