Re: [BUGS] BUG #2977: dow doesn't conform to ISO-8601

Updated version applied. I reduced the numering changes for the macros.

There was also documentation text for "dow" and a few others that said
"(for <type>timestamp</type> values only)", but in fact the field worked
for "timestamptz" and "date" too, so I removed the mentions. If people
get confused, I will come up with new wording, like "doesn't work for
interval or time", which I think is pretty obvious. I remember people
got confused in the past about this, so maybe we still need something.

---------------------------------------------------------------------------

Bruce Momjian wrote:
>
> I have implemented 'isodow' with the attached patch.
>
> ---------------------------------------------------------------------------
>
> Peter Eisentraut wrote:
> > Am Mittwoch, 7. Februar 2007 11:24 schrieb Adriaan van Os:
> > > Section 9.9.1 of the Postgres docs
> > > <http://www.postgresql.org/docs/8.2/interactive/functions-datetime.html>
> > > mentions that the "week" subfield of the date_part function conforms to the
> > > ISO-8601 standard.
> >
> > I see no such claim there.
> >
> > > You can not, in the same function, ignore ISO-8601 for one subfield and
> > > follow it in another.
> >
> > I think we have pretty well shown that we can.
> >
> > > Besides, if in the same week Sunday comes before Monday, how can the result
> > > of the "week" and "dow" fields conform to each other ?
> >
> > They don't.
> >
> > > If "dow" can not be changed for reasons of backward compatibility, I
> > > suggest a new subfield "dayofweek" that does conform to the standard.
> >
> > That might be reasonable. (Or maybe "isodow".)
> >
> > --
> > Peter Eisentraut
> > http://developer.postgresql.org/~petere/
> >
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>
> --
> Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
> EnterpriseDB http://www.enterprisedb.com
>
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>
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--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://www.enterprisedb.com

+ If your life is a hard drive, Christ can be your backup. +