ADDCOLUMS in front of SUMMARIZE

[Anonymous]

Good Afternoon everyone

I have a case. I want to calculate the count of the salesperson that has sales performance beyond the budget/estimation. 

This is my initial DAX Code:

Count of Overbudget Salesperson =

var temp =

SUMMARIZE(Actual Sales table, SalespersonName,DimYearMonth[YearMonth],"tmp Actual Sales",[Actual Data],"tmp Budget Sales",[Budget Sales])

var result = CALCULATE(COUNTROWS(FILTER(tmp,[tmp Actual Sales]>[tmp Budget Sales])))
RETURN result

It doesn't give the intended result

But if I add ADD COLUMNS DAX in front of SUMMARIZE, the result will be correct. Like this:
var temp =
ADDCOLUMNS(SUMMARIZE(Actual Sales table, SalespersonName,DimYearMonth[YearMonth]),"tmp Actual Sales",[Actual Data],"tmp Budget Sales",[Budget Sales])

Why is this happening? What is the difference?

Thank you

[amitchandak · Accepted solution]

@Anonymous , do your actual data or budget data use some row context or across period values. In this case, summarize does work well, we have use addcolumns

refer this article if needed

https://www.sqlbi.com/blog/marco/2012/09/04/optimize-summarize-with-addcolumns-in-dax-ssas-tabular-dax-powerpivot/

[Anonymous]

But why does the difference of result happen whether you use ADDCOLUMNS or not?

Thank you