Обсуждение: to_date conversion semantics?
Hi,
I can't find in the Postgresql documentation the semantics that explains the following:
colin@ruby:~/workspace/eyedb$ psql
psql (8.4.4)
Type "help" for help.
colin=> select to_date('731332', 'YYMMDD');
to_date
------------
1974-02-01
(1 row)
colin=>
Thanks,
Colin
I can't find in the Postgresql documentation the semantics that explains the following:
colin@ruby:~/workspace/eyedb$ psql
psql (8.4.4)
Type "help" for help.
colin=> select to_date('731332', 'YYMMDD');
to_date
------------
1974-02-01
(1 row)
colin=>
Thanks,
Colin
On Monday 20 September 2010 7:20:29 am Colin 't Hart wrote: > Hi, > > I can't find in the Postgresql documentation the semantics that explains > the following: > > > colin@ruby:~/workspace/eyedb$ psql > psql (8.4.4) > Type "help" for help. > > colin=> select to_date('731332', 'YYMMDD'); > to_date > ------------ > 1974-02-01 > (1 row) > > colin=> > > > Thanks, > > Colin http://www.postgresql.org/docs/8.4/interactive/functions-formatting.html -- Adrian Klaver adrian.klaver@gmail.com
I must be blind, I can see the syntax but I can't see where it explains the wrapping phenomenon that I'm seeing.
Cheers,
Colin
Cheers,
Colin
On 20 September 2010 16:36, Adrian Klaver <adrian.klaver@gmail.com> wrote:
http://www.postgresql.org/docs/8.4/interactive/functions-formatting.htmlOn Monday 20 September 2010 7:20:29 am Colin 't Hart wrote:
> Hi,
>
> I can't find in the Postgresql documentation the semantics that explains
> the following:
>
>
> colin@ruby:~/workspace/eyedb$ psql
> psql (8.4.4)
> Type "help" for help.
>
> colin=> select to_date('731332', 'YYMMDD');
> to_date
> ------------
> 1974-02-01
> (1 row)
>
> colin=>
>
>
> Thanks,
>
> Colin
--
Adrian Klaver
adrian.klaver@gmail.com
On 09/20/2010 07:50 AM, Colin 't Hart wrote: > I must be blind, I can see the syntax but I can't see where it explains > the wrapping phenomenon that I'm seeing. > > Cheers, > > Colin > My turn to be blind, what wrapping ? :) -- Adrian Klaver adrian.klaver@gmail.com
The 32nd of Undecember (!) turning into the 1st of February of the next year... instead of throwing an exception like I expect. On 20 September 2010 21:02, Adrian Klaver <adrian.klaver@gmail.com> wrote: > On 09/20/2010 07:50 AM, Colin 't Hart wrote: >> >> I must be blind, I can see the syntax but I can't see where it explains >> the wrapping phenomenon that I'm seeing. >> >> Cheers, >> >> Colin >> > > My turn to be blind, what wrapping ? :) > > > -- > Adrian Klaver > adrian.klaver@gmail.com >
"Colin 't Hart" <colinthart@gmail.com> writes: > The 32nd of Undecember (!) turning into the 1st of February of the > next year... instead of throwing an exception like I expect. As mentioned previously, to_date isn't the tool to use if you want a strict conversion --- it's designed to be rather, um, liberal. Some people think that accepting dates like June 31st is a feature. regards, tom lane
On 20/09/10 20:18, Colin 't Hart wrote: > The 32nd of Undecember (!) turning into the 1st of February of the > next year... instead of throwing an exception like I expect. What Tom said, but it's presumably using mktime(...) somewhere internally. perl -MPOSIX -e 'print scalar gmtime(mktime(0,0,0,32,13-1,73)),"\n"' Fri Feb 1 00:00:00 1974 http://perldoc.perl.org/POSIX.html#mktime http://linux.die.net/man/3/mktime -- Richard Huxton Archonet Ltd