Need help writing this simple logic in DAX

[Anonymous]

Heres the logic:

For each ContactID in ContactID column:

    Count Distinct ( ProductIDs).

Next ContactID

My data looks like this (well this is a mockup...):

ContactID	ProductID
ID1	A
ID1	A
ID1	A
ID1	B
ID1	B
ID2	A
ID2	B
ID2	C
ID1	A
ID1	B

So the answer is:

ContactID	CountDistinct	Values
ID1	2	(A, B)
ID2	3	(A, B, C)

A Calculated Column would look like this

ContactID	ProductID	My Column
ID1	A	2
ID1	A	2
ID1	A	2
ID1	B	2
ID1	B	2
ID2	A	3
ID2	B	3
ID2	C	3
ID1	A	2
ID1	B	2

Edit: need to use a calculated column, not a measure

FYI - Doing this in SSAS Tabular not Power BI, but I assume it's the same.

Thanks.

[vanessafvg]

@Anonymous are you wanting your values to be concatenated ie. a,b,c?

[Anonymous]

@vanessafvg No I've edited my post. I want the discinct count of productID's per each distinct contactID 

[kschaefers]

You could either create a measure using DISTINCTCOUNT(ColumnName) or alternatively create a new table using SUMMARIZECOLUMNS (See more details here: https://msdn.microsoft.com/en-us/library/mt163696.aspx)

[Anonymous]

@kschaefers Now that I think about, this will actually need to be a calculated column, it cannot be a separate table though. The problem is that I need separate distinct counts for each contactID. I cannot just use distinctcount(ProductID) because that would ignore the ContactID column.

[kschaefers · Accepted solution]

Then you can use this Calculated Column Formula:

My Column = CALCULATE(DISTINCTCOUNT(Table1[ProductID]),FILTER(Table1,Table1[ContactID]=EARLIER(Table1[ContactID])))