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Anonymous's avatar
Anonymous
Not applicable
6 years ago
Solved

TopN based on Measure instead of Column

Hi everyone, I am struggling with the TopN function and I hope you can help me out. Data: event registration data, with calculated columns for CY (current year) and LY (Last year). I also created a ...
  • Anonymous's avatar
    Anonymous
    6 years ago

    This piece of code:

     

    Largest Deficit Region = 
CALCULATE(
    SELECTEDVALUE('Sample Data'[Region]),
    TOPN(1,
         'Sample Data',
         [CY - LY Reg Diff],
         ASC
    )
)

     

    returns BLANK because SELECTEDVALUE returns BLANK when there is more than 1 region returned.

     

    Change the expression under CALCULATE to show the number of regions - distinctcount( 'sample data'[region] ) - and you'll see it's not 1.

     

    Please read this: https://dax.guide/topn/

     

    Best

    D

Greg_Deckler's avatar
Greg_Deckler
Icon for Community Champion rankCommunity Champion
6 years ago

Could you use ADDCOLUMNS to add your TOPN column and then take the MIN or MAX of it?

Anonymous's avatar
Anonymous
Not applicable
6 years ago

Hi, I must be doing something wrong here. I added ADDCOLUMNS to the expression, but now it looks like it's using it as multiple columns- I thought that I only added one. 😞 

= CALCULATE( SELECTEDVALUE('Sample Data'[Region]), ADDCOLUMNS('Sample Data',"Top N",TOPN(1,'Sample Data',[CY - LY Reg Diff],ASC)))
Error message: "The expression referrs to multiple columns. Multiple columns cannot be converted to a scalar value."
 
I must be missing a step or three. 
  • Anonymous's avatar
    Anonymous
    Not applicable
    6 years ago

    This piece of code:

     

    Largest Deficit Region = 
CALCULATE(
    SELECTEDVALUE('Sample Data'[Region]),
    TOPN(1,
         'Sample Data',
         [CY - LY Reg Diff],
         ASC
    )
)

     

    returns BLANK because SELECTEDVALUE returns BLANK when there is more than 1 region returned.

     

    Change the expression under CALCULATE to show the number of regions - distinctcount( 'sample data'[region] ) - and you'll see it's not 1.

     

    Please read this: https://dax.guide/topn/

     

    Best

    D

    • Anonymous's avatar
      Anonymous
      Not applicable
      6 years ago

      Thank you- I was actually able to get it to work!