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

On 29-8-2020 11:07, Chris Elvidge 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.
> 
> 
> 

$ date -d "2021-01-01" +"%A %G-%V"
Friday 2020-53
$ date -d "2021-01-04" +"%A %G-%V"
Monday 2021-01