DAX to find where it does not exist

[Aree]

The problem i am attempting to solve is simple to do in SQL but I would like to derive the DAX equivalent.

I want to count the number of users who do not have a score in the Results Table. 

These tables are link via the UID field. 
I'm sure the solution is simple but i just can't conceptualize it 😞

[OwenAuger · Accepted solution]

@Aree

A simple measure that should achieve this is:

Count of Users Without Score =
COUNTROWS (
    EXCEPT (
        VALUES ( Users[UID] ),
        VALUES ( Results[UID] )
    )
)

This would respond to any filters on either Users or Results tables.

[Aree]

Thank you @OwenAuger

I needed to also add a filter but the end DAX measure looks like this

Calculate (
            CountRows (
                       Except( Values('Users'[UID]), Values('Results'[UID])))
            , 'Results'[Exam] = "English")  

So i can count where the User does not have an enlgish score. 

Much Appreciated.

[Hardik]

https://community.powerbi.com/t5/Desktop/DAX-equivalent-of-NOT-EXISTS/td-p/56673

 hope this provides you with the solution