Named calculation on a fact table

Hello,

I have a measure, MyMeasure, whose measure group is linked to two dimensions: Date and DateType. These correspond to a fact table called FactMyMeasure and two dimension tables DimDate and DimDateType in my Data Source view.The fact table, FactMyMeasure, has 3 columns:

Date Key
DateType Key
MyMeasure

One of these, however, is not a regular column; [DateType Key] is actually a named calculation whose code looks like this:

        (
            SELECT dates.[DateType Key]
            FROM [Cube].[DimDate] AS dates
            WHERE dates.[Date Key] = [Cube].[FactMyMeasure].[Date Key]
        )

This gives the impression that MyMeasure depends on two dimensions, when in reality DateType is a dummy that's generated through the value of Date.

I have a problem when trying to process the cube on a populated Data Source:
The multi-part identifier "Cube.FactMyMeasure.Date Key" could not be bound.

I believe this is because the data used to populate FactMyMeasure comes from multiple different Views, each corresponding to a different partition. Therefore, [Cube].[FactMyMeasure].[Date Key] appears to not exist as the name of the table changes from one View to the other.

Any clues on how I could work around this problem?