How to filter all rows attached to an ID value

[EVG-Questions]

I'm trying to find all ID values containing a certain value. Example given here:

 In this example I need to find all ID values that contain a "D" and then assign a "1" to all rows with one of those ID values, including rows that don't actually contain "D".

[PaulDBrown · Accepted solution]

Try this measure:

Countrows D =
VAR _D =
    CALCULATETABLE (
        VALUES ( 'FactTable'[Cat1] ),
        ALLEXCEPT ( FactTable, FactTable[ID] )
    )
RETURN
    IF ( "D" IN _D, 1, 0 )

 If you don't need the rows with 0, close the brackets after the 1 in the return IF expression

[EVG-Questions]

Hi @PaulDBrown! 
If it's not too much to ask, could you take a look at the question I posted here. I'm still having trouble with it. Thanks!

[EVG-Questions]

Thank you!

This does seem to work. I have some additional questions but I'll make a seperate message for those.