Re: OT weekdates in MSSQL [Re: just to laugh]

Jim H <[email protected]> Sat, 29 Aug 2020 16:15:26 +0000
Newsgroups comp.databases.mysql
Organization Forte - www.forteinc.com
Message-ID <[email protected]>
On Sat, 29 Aug 2020 10:07:45 +0100, in <[email protected]>,
Chris Elvidge <[email protected]> wrote:

>On 29/08/2020 08:05 am, Luuk wrote:
>> On 28-8-2020 16:38, Ammammata wrote:
>>> tried this with MS SQL
>>>
>>> select DATEPART(wk, '20210101')
>>> select DATEPART(wk, '20210102')
>>> select DATEPART(wk, '20210103')
>>> select DATEPART(wk, '20210104')
>>> select DATEPART(wk, '20210105')
>>> select DATEPART(wk, '20210106')
>>>
>>> result
>>>
>>> 1
>>> 1
>>> 2
>>> 2
>>> 2
>>> 2
>>>
>>> https://en.wikipedia.org/wiki/ISO_8601#Week_dates
>>>
>>>
>> 
>> select DATEPART(isowk, '20210101')
>> select DATEPART(isowk, '20210102')
>> select DATEPART(isowk, '20210103')
>> select DATEPART(isowk, '20210104')
>> select DATEPART(isowk, '20210105')
>> select DATEPART(isowk, '20210106')
>> 
>> result
>> 
>> 53
>> 53
>> 53
>> 1
>> 1
>> 1
>> 
>> https://docs.microsoft.com/en-us/sql/t-sql/functions/datepart-transact-sql?view=sql-server-ver15 
>> 
>> 
>
>IIRC iso weeks start on Monday, ordinary weeks start on Sunday.
>Look at the linux 'date' command, specifically %V (%G) and %U
>That may suggest why 20210101 is isoweek 53.

As I (think I) recall... you can get the ISO week by counting
Thursdays in the year to date.
-- 
Jim H