while using date_trunc('week', some_date) to get the date of the first day of the week I noticed that it was working as expected: Monday is considered the start of the week. I assume this depends on some locale setting, but I can't figure out which it is, so I can make sure this is not "accidently" changed. I tried changing LC_TIME (American_America) but that still returned Monday as the first day (my understanding is that in the States Sunday is considered the start of the week)
Any pointers are appreciated (did I miss it in the manual?)
Regards Thomas
I don't understand how date_trunc is giving you the day of the week. As far as I'm aware it only reduces the precision of the date/time. What I imagine you'd use is: extract(DOW from some_date). This won't be locale-dependant. It will always be 0 (Sunday) - 6 (Saturday). There is another way to get the day of the week which is to_char(some_date, 'D') which is numbered 1 (Sunday) to 7 (Saturday).