X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org
Received: from localhost (av.hub.org [200.46.204.144])
	by svr1.postgresql.org (Postfix) with ESMTP id 09076D8A8C;
	Sat, 10 Sep 2005 11:42:17 -0300 (ADT)
Received: from svr1.postgresql.org ([200.46.204.71])
	by localhost (av.hub.org [200.46.204.144]) (amavisd-new, port 10024)
	with ESMTP id 18140-05; Sat, 10 Sep 2005 14:42:13 +0000 (GMT)
Received: from tigger.fuhr.org (tigger.fuhr.org [63.214.45.158])
	by svr1.postgresql.org (Postfix) with ESMTP id 5097CD78F2;
	Sat, 10 Sep 2005 10:06:27 -0300 (ADT)
Received: from winnie.fuhr.org (winnie.fuhr.org [10.1.0.1])
	by tigger.fuhr.org (8.13.3/8.13.3) with ESMTP id j8AD6S3g040369
	(version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK);
	Sat, 10 Sep 2005 07:06:30 -0600 (MDT)
	(envelope-from mfuhr@winnie.fuhr.org)
Received: from winnie.fuhr.org (localhost [127.0.0.1])
	by winnie.fuhr.org (8.13.3/8.13.3) with ESMTP id j8AD6RGn045646;
	Sat, 10 Sep 2005 07:06:28 -0600 (MDT)
	(envelope-from mfuhr@winnie.fuhr.org)
Received: (from mfuhr@localhost)
	by winnie.fuhr.org (8.13.3/8.13.3/Submit) id j8AD6R8p045645;
	Sat, 10 Sep 2005 07:06:27 -0600 (MDT) (envelope-from mfuhr)
Date: Sat, 10 Sep 2005 07:06:27 -0600
From: Michael Fuhr <mike@fuhr.org>
To: "Marc G. Fournier" <scrappy@postgresql.org>
Cc: pgsql-performance@postgresql.org
Subject: Re: CHECK vs REFERENCES
Message-ID: <20050910130627.GA45586@winnie.fuhr.org>
References: <20050910001821.E1170@ganymede.hub.org>
	<20050910034907.GA40382@winnie.fuhr.org>
	<20050910010141.O1170@ganymede.hub.org>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20050910010141.O1170@ganymede.hub.org>
X-Virus-Scanned: by amavisd-new at hub.org
X-Spam-Status: No, hits=0.005 required=5 tests=[AWL=0.005]
X-Spam-Level: 
X-Archive-Number: 200509/123
X-Sequence-Number: 14431

On Sat, Sep 10, 2005 at 01:03:03AM -0300, Marc G. Fournier wrote:
> On Fri, 9 Sep 2005, Michael Fuhr wrote:
> >INSERT INTO test_check SELECT 1 FROM generate_series(1, 100000);
> >INSERT 0 100000
> >Time: 3492.344 ms
> >
> >INSERT INTO test_fk SELECT 1 FROM generate_series(1, 100000);
> >INSERT 0 100000
> >Time: 23578.853 ms
> 
> Yowch, I expected CHECK to be better ... but not so significantly ... I 
> figured I'd be saving milliseconds, which, on a busy server, would add up 
> fast ... but not 10k' of milliseconds ...

Results will differ depending on the table structure: if you're
indexing ten columns and have five triggers then the foreign key
check will have less of an overall impact.

-- 
Michael Fuhr