Re: Error in 7.2

heh.. Your right.  With the 7.1 results I didn't notice the date was
missing.
--
Rod Taylor

This message represents the official view of the voices in my head

----- Original Message -----
From: "Tom Lane" <tgl@sss.pgh.pa.us>
To: <rbt@barchord.com>
Cc: <pgsql-hackers@postgresql.org>; "Thomas Lockhart"
<lockhart@fourpalms.org>
Sent: Wednesday, January 16, 2002 3:44 PM
Subject: Re: [HACKERS] Error in 7.2


> rbt@barchord.com writes:
> > select now() + cast('71 minutes' as interval) as case1
> >       , cast('71 minutes' as interval) + now() as case2
> >       , now() + cast('5 minutes' as interval) as case3
> >       , cast('5 minutes' as interval) + now() as case4
> >       , now();
>
> > The above works as expected in 7.1, but in 7.2 case1 and case2
have
> > different values.
>
> No, it doesn't behave the way I'd expect in 7.1, either:
>
> test71=# select version();
>                              version
> ------------------------------------------------------------------
>  PostgreSQL 7.1.3 on hppa2.0-hp-hpux10.20, compiled by GCC 2.95.3
> (1 row)
>
> test71=# select now() + cast('71 minutes' as interval) as case1;
>          case1
> ------------------------
>  2002-01-16 16:44:58-05
> (1 row)
>
> test71=# select  cast('71 minutes' as interval) + now() as case2;
>   case2
> ----------
>  16:45:06
> (1 row)
>
> The operator being selected in the second case is interval_pl_time;
> apparently we don't have interval + timestamp, and that's as close
> as 7.1 can find.  Of course the result of now() is first converted
> to time.
>
> In current sources I get
>
> regression=# select version();
>                             version
> ---------------------------------------------------------------
>  PostgreSQL 7.2b5 on hppa-hp-hpux10.20, compiled by GCC 2.95.3
> (1 row)
>
> regression=# select now() + cast('71 minutes' as interval) as case1;
>             case1
> ------------------------------
>  2002-01-16 16:46:45.37056-05
> (1 row)
>
> regression=# select  cast('71 minutes' as interval) + now() as
case2;
>         case2
> ---------------------
>  2002-01-16 01:11:00
> (1 row)
>
> The operator being selected here is timedate_pl, which seems a
peculiar
> choice also.  (now() is coerced to date, natch.)  I'd say this is
> marginally better than 7.1's choice, but why the change in behavior?
>
> Of course the real problem is the lack of specific interval +
timestamp
> addition operators.  I don't think we should hold up 7.2 release
(and
> force another initdb) to fix this, considering that 7.1 wasn't any
> better.  Put it on TODO for 7.3, instead.
>
> Comments?
>
> regards, tom lane
>