Re: [BUGS] BUG #1563: wrong week returnded by date_trunc('week',

Robert Creager wrote:
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> When grilled further on (Tue, 29 Mar 2005 07:43:53 +0200),
> Dirk Raetzel <d00273(at)spaetzle(dot)de> confessed:
>
> >
> >
> > On Mon, 28 Mar 2005, Bruce Momjian wrote:
> >
> > > I have developed a patch to fix the problem. Instead of changing the
> > > API, I added code to decrement the year when the week number was 53 and
> > > the month was January. It corrected the problem:
> >
> > The problem arises as well when week number is 52 as in '2006-01-01'.
>
> Try these at the least:
>
> select date_trunc_week( '2004-01-01' ); -- should be 2003-12-29 00:00:00
> select date_trunc_week( '2005-01-01' ); -- should be 2004-12-27 00:00:00
> select date_trunc_week( '2005-06-01' ); -- should be 2005-05-30 00:00:00
> select date_trunc_week( '2006-01-01' ); -- should be 2005-12-26 00:00:00
> select date_trunc_week( '2007-01-01' ); -- should be 2007-01-01 00:00:00
>
> If it helps, look earlier in this thread for a (overly complicated?) version in
> plpgsql.

Wow, an early January date can be part of the 52nd week of the previous
year too.

Here is a new patch, with a documentation mention.

--
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