Top N error: The expression refers to multiple columns.

[floralau]

Hi all,

I am new to power bi and faced some difficulties.

What's wrong with my following code?

measure =

TOPN(

3,

'Succesful Rate',

'Succesful Rate'[Channel],0

)

The error message is: The expression refers to multiple columns. Multiple columns cannot be converted to a scalar value.

Also, what i would like to do is to find out the number of different strings in "Channel".

"Channel" contains "aaa","aaa","aaa","bbb","bbb","ccc","ddd","ddd" etc.

Thanks for your help!

[PhilipTreacy · Accepted solution]

Hi @floralau 

Download example PBIX file with the following code

TOPN returns a table which is why you are getting the error about 'multiple columns'.  I guess you are trying to create a measure, but a measure must be a single value, it can't hold a table.

To count the number of different strings use this measure

Number of Diff Strings = DISTINCTCOUNT('Successful Rate'[Channel])

Regards

Phil

[floralau]

Thanks so much for your help!