From: Bruce Momjian <pgman@candle.pha.pa.us>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Rod Taylor <pg@rbt.ca>
Cc: Markus Bertheau <twanger@bluetwanger.de>
Cc: PgSQL - SQL <pgsql-sql@postgresql.org>
Subject: Re: empty view, replace view, column type change?
Date: Fri, 24 Jun 2005 00:32:15 -0400 (EDT)
Message-ID: <200506240432.j5O4WF026888@candle.pha.pa.us> (raw)
In-Reply-To: <8931.1119565282@sss.pgh.pa.us>
Tom Lane wrote:
> > If you SELECT 'abc'::varchar(6)::varchar, the end type is varchar(6).
>
> Yeah, this is exactly what's happening --- if you look at gram.y,
> LOCALTIMESTAMP is expanded to "'now'::text::timestamp(6)". I am
> unconvinced that the (6) is a very good idea though. The code says
>
> /* SQL99 mandates a default precision of 6 for timestamp.
> * Also, that is about as precise as we will get since
> * we are using a microsecond time interface.
> * - thomas 2001-12-07
> */
> d->typmod = 6;
>
> but it doesn't seem to me to follow from what the spec says that we need
> to explicitly cast the result of now() to six places. As long as it's
> coming from gettimeofday it can't have more than 6 places anyway, and so
> we might as well save the extra coercion step. (The parser *will* tack
> on a separate coercion function call when presented with this parse
> tree.)
>
> In short, I'm inclined to remove the above-quoted lines, and similarly
> for CURRENT_TIME, CURRENT_TIMESTAMP, and LOCALTIME. Thoughts?
Agreed. That "6" bothered me too when I was cleaning up the timestamp
code a while back.
--
Bruce Momjian | http://candle.pha.pa.us
pgman@candle.pha.pa.us | (610) 359-1001
+ If your life is a hard drive, | 13 Roberts Road
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To: pgsql-sql@postgresql.org
Cc: pgman@candle.pha.pa.us, tgl@sss.pgh.pa.us, pg@rbt.ca, twanger@bluetwanger.de
Subject: Re: empty view, replace view, column type change?
In-Reply-To: <200506240432.j5O4WF026888@candle.pha.pa.us>
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