Received: from home.priority.net (home.priority.net [204.27.108.182])
	by hub.org (8.9.3/8.9.3) with ESMTP id JAA15581
	for <pgsql-sql@postgreSQL.org>; Tue, 17 Aug 1999 09:02:37 -0400 (EDT)
	(envelope-from tpham@mail.priority.net)
Received: by home.priority.net with Internet Mail Service (5.5.2448.0)
	id <QT103NVK>; Tue, 17 Aug 1999 08:18:56 -0500
Message-ID: <551413BBBB03D111BF880060B01AACCE139F34@home.priority.net>
From: "Pham, Thinh" <tpham@mail.priority.net>
To: "'pgsql-sql@postgreSQL.org'" <pgsql-sql@postgreSQL.org>
Subject: RE: [SQL] datediff function
Date: Tue, 17 Aug 1999 08:18:55 -0500
MIME-Version: 1.0
X-Mailer: Internet Mail Service (5.5.2448.0)
Content-Type: text/plain;
	charset="iso-8859-1"

What happen if i just want to compare using minute only or hour only instead
of day? Is there a function to do that or is postgres only work in day?

T.


> -----Original Message-----
> From: Herouth Maoz [mailto:herouth@oumail.openu.ac.il]
> Sent: Tuesday, August 17, 1999 6:05 AM
> To: tjk@tksoft.com; tpham@mail.priority.net
> Cc: pgsql-sql@postgreSQL.org
> Subject: Re: [SQL] datediff function
> 
> 
> At 02:26 +0300 on 17/08/1999, tjk@tksoft.com wrote:
> 
> 
> >
> > I think what you are looking for is age()
> > E.g.
> >
> > "update schedule set purged = 0 where age('now',dayin) > 
> timespan('30
> >days'::reltime)"
> >
> > Presuming a table such as this:
> >
> > create table schedule (purged int, dayin datetime);
> >
> > This replaces "day" and "timein" with "dayin."
> 
> Basically correct, but if there is an index on dayin, it 
> won't be used. The
> best query to do would be
> 
> WHERE dayin > 'now'::datetime - '30 days'::timespan;
> 
> Herouth
> 
> --
> Herouth Maoz, Internet developer.
> Open University of Israel - Telem project
> http://telem.openu.ac.il/~herutma
> 
> 
>