Message-ID: <008c01c3e565$7c2baac0$d4c7a8c0@raman>
From: "Raman Garg" <ramang@smartdatainc.com>
To: "Tom Lane" <tgl@sss.pgh.pa.us>
Cc: <pgsql-sql@postgresql.org>
References: <003c01c3e55e$54b12d50$d4c7a8c0@raman>
	<8028.1075269512@sss.pgh.pa.us>
Subject: Re: Query TIME ZONE 
Date: Wed, 28 Jan 2004 11:39:23 +0530
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Thanks Tom it worked  for me...
yes I got it wrong.. thanks for the correction.

thanks a lot..
-- Raman

----- Original Message ----- 
From: "Tom Lane" <tgl@sss.pgh.pa.us>
To: "Raman" <ramang@smartdatainc.com>
Cc: <pgsql-sql@postgresql.org>
Sent: Wednesday, January 28, 2004 11:28 AM
Subject: Re: [SQL] Query TIME ZONE


> "Raman" <ramang@smartdatainc.com> writes:
> > [ okay: ]
> > "select current_time AT TIME ZONE INTERVAL '+5:30'"
> > [ not okay: ]
> > "select current_time AT TIME ZONE INTERVAL time_difference from
customer_events"
>
> "TIME ZONE INTERVAL" is not a SQL construct.  You have misunderstood the
> interaction of two different SQL constructs:
> timestamp AT TIME ZONE timezonespec
> INTERVAL 'interval-literal'
> One of the possible forms of "timezonespec" in the AT TIME ZONE operator
> is an interval value, so your first example works fine.  Your second
> example does not work because the INTERVAL 'foo' construct is only for
> simple literal constants.
>
> > here : time_difference - is my varchar column in the table
customer_events.
>
> Why are you using varchar rather than an interval column?  An interval
> value would work directly in this construct and would provide some
> checking that entered values are sane.
>
> If you are absolutely intent on using varchar as the column datatype,
> you can do a run-time cast like this:
> select current_time AT TIME ZONE "interval"(time_difference) from
customer_events
> but don't complain when the query fails because some rows contain
> time_difference strings that don't look like legal interval values...
>
> regards, tom lane
>