Daniel Schuchardt <daniel_schuchardt(at)web(dot)de> writes:
> LOLL2=# SELECT to_char('2007-12-31'::DATE, 'YYYYIW');
> to_char
> ---------
> 200701
> (1 row)
> 2007-12-31 should be week 2008-01
No, it shouldn't. YYYY is defined to deliver calendar year.
For ISO year use IYYY.
regards, tom lane