Unexpected return from TREATAS function

Hi gvg 

There are two records on 2018/1/1 with the same product id. The amount in the highlighted row is from John's amount rather than Peter's amount. In this measure, TREATAS returns all the values exist in both Managers table's Mgr column and Sales table's Manager column, so the result is John and Sam. It calculates the total amount of John and Sam's sales. 

In image below, I use CONCATENATEX to combine the results returned by TREATAS(VALUES(Managers[Mgr]),Sales[Manager]) part. You will find Peter is excluded as expected. 

TestTreatas5 = CONCATENATEX(TREATAS(VALUES(Managers[Mgr]),Sales[Manager]),[Manager],", ")

In your second measure 

TestTreatas5 = 
CALCULATE(SUM(Sales[Amount]),VALUES(Sales[Manager]),TREATAS(VALUES(ManagerTable[Manager]),Sales[Manager])) 

VALUES(Sales[Manager]) part works as an additional filter in CALCULATE expression. On rows having "Peter", VALUES(Sales[Manager]) returns "Peter" while "Peter" doesn't exist in the result of TREATAS part, so the filtered result is blank.

Reference:

TREATAS – DAX Guide

A Deep Dive Into The TREATAS DAX Function In Power BI | Enterprise DNA

Best Regards,
Community Support Team _ Jing
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