Обсуждение: select to_char(current_timestamp, 'YYYY-WW');

Hello,

sorry for the stupid question, but why has the week number changed
from 44 to 45 this night? It is Friday, 2010-11-05 01:10, but I get now:

pref=> SELECT to_char(current_timestamp, 'YYYY-WW');
 to_char
---------
 2010-45
(1 row)

pref=> SELECT CURRENT_DATE;
    date
------------
 2010-11-05
(1 row)

pref=> SELECT CURRENT_TIME;
      timetz
-------------------
 01:12:00.65546+01
(1 row)

# date
Fri Nov  5 01:13:57 CET 2010
# cat /etc/*release
CentOS release 5.5 (Final)
# rpm -qa|grep -i postgres
compat-postgresql-libs-4-1PGDG.rhel5
postgresql-libs-8.4.5-1PGDG.rhel5
compat-postgresql-libs-4-1PGDG.rhel5
postgresql-docs-8.4.5-1PGDG.rhel5
postgresql-8.4.5-1PGDG.rhel5
postgresql-libs-8.4.5-1PGDG.rhel5

Regards
Alex

Alexander Farber <alexander.farber@gmail.com> writes:
> sorry for the stupid question, but why has the week number changed
> from 44 to 45 this night?

WW is defined as starting the first week on the first day of the year.
2010 started on a Friday so the week number increments on Fridays.

There are some other format codes with different behavior ...

            regards, tom lane

On Fri, Nov 5, 2010 at 1:21 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> WW is defined as starting the first week on the first day of the year.
> 2010 started on a Friday so the week number increments on Fridays.
>
> There are some other format codes with different behavior ...

Thank you, that is what I thought

But is there a format code for a week starting on Sunday or Monday?

Sorry, I can't find it at
http://www.postgresql.org/docs/8.4/interactive/functions-formatting.html

Regards
Alex

I will try YYYY-IW

On Fri, Nov 5, 2010 at 1:28 AM, Alexander Farber
<alexander.farber@gmail.com> wrote:
> But is there a format code for a week starting on Sunday or Monday?
>
> Sorry, I can't find it at
> http://www.postgresql.org/docs/8.4/interactive/functions-formatting.html