Function 'WEEKNUM' is not allowed as part of calculated column DAX expressions on DirectQuery

[vopatel]

I want to use this function to plot a chart for weekly sales and getting this error. I dont know how I can use Power Query as suggested here or whether it is a right answer.

http://community.powerbi.com/t5/Desktop/Error-Function-WEEKNUM-is-not-allowed-as-part-of-calculated/...

Can someone point me to right place?

Thank You,

Vishal

[v-qiuyu-msft · Accepted solution]

Hi @vopatel,

To return weeknum values for dates in Query Editor, we can create a custom column below: 

But Please note, as it's DirectQuery mode, it's not able to apply this change after add this custom column, you can see below message when you apply query: 

In your scenario, I would suggest you use T-SQL query to return weeknum values: 

Best Regards,
Qiuyun Yu