Received: from megazone.bigpanda.com (megazone.bigpanda.com [63.150.15.178])
	by postgresql.org (8.11.3/8.11.4) with ESMTP id g16FU2E58706
	for <pgsql-sql@postgresql.org>; Wed, 6 Feb 2002 10:30:03 -0500 (EST)
	(envelope-from sszabo@megazone23.bigpanda.com)
Received: by megazone.bigpanda.com (Postfix, from userid 1001)
	id 68B32D5F9; Wed,  6 Feb 2002 07:29:56 -0800 (PST)
Received: from localhost (localhost [127.0.0.1])
	by megazone.bigpanda.com (Postfix) with ESMTP
	id 5E6185BF8; Wed,  6 Feb 2002 07:29:56 -0800 (PST)
Date: Wed, 6 Feb 2002 07:29:56 -0800 (PST)
From: Stephan Szabo <sszabo@megazone23.bigpanda.com>
To: Isabelle Brette <isabelle@apartia.fr>
Cc: <pgsql-sql@postgresql.org>
Subject: Re: indexes
In-Reply-To: <20020205170524.GA1990@aparima.com>
Message-ID: <20020206072840.L16466-100000@megazone23.bigpanda.com>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
X-Archive-Number: 200202/68
X-Sequence-Number: 6498


On Tue, 5 Feb 2002, Isabelle Brette wrote:

> As you may also guess, making straight indexes does not work (I still
> have this damn Seq Scan while EXPLAINing). For the date, I tried this :
>
> 	create index sess_created on sessions (to_char(created,'YYYY/MM'));
>
> but I get a parse error near "'". What do I have wrong, as the query
> seems right ? Is it because of the non-column argument ?

For a functional index that you want to pass constants to, right now you'd
need to make a cacheable function that takes created in this case and
returns the to_char(created, 'YYYY/MM') and then use that in the index and
query.