Received: from makus.postgresql.org (makus.postgresql.org [98.129.198.125])
	by mail.postgresql.org (Postfix) with ESMTP id 92D9F19F5A50
	for <pgsql-sql@postgresql.org>; Wed,  8 Feb 2012 21:51:45 -0400 (AST)
Received: from plane.gmane.org ([80.91.229.3])
	by makus.postgresql.org with esmtp (Exim 4.72)
	(envelope-from <sql-pgsql-sql@m.gmane.org>) id 1RvJAk-00057D-Gv
	for pgsql-sql@postgresql.org; Thu, 09 Feb 2012 01:51:44 +0000
Received: from list by plane.gmane.org with local (Exim 4.69)
	(envelope-from <sql-pgsql-sql@m.gmane.org>) id 1RvJAU-0003un-Uz
	for pgsql-sql@postgresql.org; Thu, 09 Feb 2012 02:51:26 +0100
Received: from d223152.adsl.hansenet.de ([80.171.223.152])
	by main.gmane.org with esmtp (Gmexim 0.1 (Debian))
	id 1AlnuQ-0007hv-00
	for <pgsql-sql@postgresql.org>; Thu, 09 Feb 2012 02:51:26 +0100
Received: from tim by d223152.adsl.hansenet.de with local (Gmexim 0.1
 (Debian))
	id 1AlnuQ-0007hv-00
	for <pgsql-sql@postgresql.org>; Thu, 09 Feb 2012 02:51:26 +0100
X-Injected-Via-Gmane: http://gmane.org/
Mail-Followup-To: pgsql-sql@postgresql.org
To: pgsql-sql@postgresql.org
From: Tim Landscheidt <tim@tim-landscheidt.de>
Subject: Re: time interval math
Date: Thu, 09 Feb 2012 01:51:10 +0000
Organization: <URI:http://www.tim-landscheidt.de/>
Lines: 26
Message-ID: <m3d39oixkh.fsf@passepartout.tim-landscheidt.de>
References: <032001cce69c$767bc010$63734030$@com>
	<4F32DA3B.9080209@pinpointresearch.com>
	<032701cce6a3$28c8fca0$7a5af5e0$@com>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
X-Complaints-To: usenet@dough.gmane.org
X-Gmane-NNTP-Posting-Host: d223152.adsl.hansenet.de
Mail-Copies-To: never
User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.1 (gnu/linux)
Cancel-Lock: sha1:jKYBxYASW6exofT1KKiVl2UccPY=
X-Pg-Spam-Score: -1.9 (-)
X-Archive-Number: 201202/26
X-Sequence-Number: 36319

"Edward W. Rouse" <erouse@comsquared.com> wrote:

> Hehe, thanks, I played around and ended up with this:

> round(SUM(extract('epoch' from (time_out - time_in))))

> I will have to do the division outside of the query, but that's really a
> minor issue.

You can always use subqueries.

>              Knowing the total in seconds was the big roadblock. And
> converting back is easier (a / 3600 + ":" + a / 60 + ":" + a % 60)
> [...]

PostgreSQL has also:

| tim=# SELECT 3661::TEXT::INTERVAL;
|  interval
| ----------
|  01:01:01
| (1 Zeile)

| tim=#

Tim