The expression refers to multiple columns. Multiple columns cannot be converted to a scalar value.

Hi, Anonymous ;

As mentioned , The GROUPBY function returns a table. So if grouping you can use the allexcept() function; Convert the above formula to the following format：

Number =
CALCULATE (
    COUNT ( Dim_Operator[Operator_Key),allexcept(Dim_Operator,Dim_Operator[Operator1] )
)

 
Best Regards,
Community Support Team _ Yalan Wu
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