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Date: Thu, 6 Jun 2002 15:33:30 -0700 (PDT)
From: Stephan Szabo <sszabo@megazone23.bigpanda.com>
To: Josh Berkus <josh@agliodbs.com>
Cc: Andre Schubert <andre.schubert@km3.de>,
	<pgsql-sql@postgresql.org>
Subject: Re: Indexing timestamps
In-Reply-To: <200206061041.52753.josh@agliodbs.com>
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On Thu, 6 Jun 2002, Josh Berkus wrote:

>
> Stephan,
>
> > Unfortunately you can't do that in that sort of syntax.  You'll
> > need to create a function that returns the month and is marked
> > as iscachable and use that function in the index creation and
> > query.
>
> Hmmm.  I take it that NOW() is not ISCACHABLE, and that's Andre's indexing
> problem?   What would be the pitfall of creating an alternate version of
> NOW() that ISCACHABLE?

I believe it was not marked as iscachable.  I think it's now marked as
static in dev sources which I would guess would mean that it could
consider an index scan.  I think with care an iscachable function that
just called now() would probably be safe for interactive queries.