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AaronRogers3's avatar
AaronRogers3
Helper I
8 years ago
Solved

Week commencing in DAX

Hi   Does anyone know the DAX for displaying the Week Commencing date?   I am working on a service desk based on tickets and we have a column for the date received of the ticket.   Now i would ...
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  • TomMartens's avatar
    TomMartens
    8 years ago

    Hey,

     

    just try this "simple" DAX statement

    SoWDate = 'Calendar'[Date]  - WEEKDAY('Calendar'[Date],2) +1

    The second parameter of the WEEKDAY()-function indicates if Sunday or Monday is your first day of the week, for me this works like a charm, maybe you have to use a different correction part.

     

    Just using your Date column and the "Day of Week" column helps to adjust the above mentioned formula if necessary.

     



    and this calculates the End Date of the week

    EoWDate = 'Calendar'[Date] + 7 - WEEKDAY([DATE],2)

     

    Hope this helps

    Regards 

Anonymous's avatar
Anonymous
Not applicable
8 years ago

This is great. Could someone please explain the logic behind this.

TomMartens's avatar
TomMartens
Super User
8 years ago

Hey,

 

thanks for your kind words!

 

The thinking (not sure if Mr Spock would call this logic) behind this is as follows:

  • A week spans 7 days
  • Each day belongs to a single week
  • If my week starts on Monday Weekday("2018-07-04",2) returns 3, a Wednesday is the 3rd day of a week
  • The date of the starting week is calculating like this: Subtracting 3 Adding 1 from "2018-07-04" returns the date of the Monday closest to the date in question "2018-07-04"
  • A similar logic is used to calculate the date of the next Sunday

 

Hopefully this explains the reasoning behind both DAX statements a little better.

 

Regards

Tom

  • KenSkinner's avatar
    KenSkinner
    Helper I
    7 years ago

    Brilliant!  Spock would be proud.  Straight forward logic and you can change the number for subtraction and addition by multiples of 7 to get the starting/ending dates for any number of weeks prior or future.  Thanks!