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richard-powerbi's avatar
richard-powerbi
Post Patron
6 years ago
Solved

Overwrite data from different fact table when available

How do I create a measure or a table with DAX to get calculated Table 3? And how would I do it if I wanted just the measure for Value of Table 3? Assuming I have common dimensions. So when data ex...
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  • AlB's avatar
    AlB
    6 years ago

    richard-powerbi 

    Assuming the field in the visual is the TableX[Id]:

    Measure =
VAR valT2_ =
    LOOKUPVALUE ( Table2[Value], Table2[Id], SELECTEDVALUE ( TableX[Id] ) )
RETURN
    IF (
        ISBLANK ( valT2 ),
        LOOKUPVALUE ( Table1[Value], Table1[Id], SELECTEDVALUE ( TableX[Id] ) ),
        valT2_
    )

     

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    Cheers 

richard-powerbi's avatar
richard-powerbi
Post Patron
6 years ago

I know this.... but why do I always get a PQ solution when I ask a DAX solution? 😞 I want to keep them as separate tables because they are different processes.

Anonymous's avatar
Anonymous
Not applicable
6 years ago
You get a PQ solution because DAX solutions will be slower if you start creating measures like the above. As for tables.... yes, you can create them in DAX but it's much better to prepare your data in advance, before it gets loaded into the model. To calculate moderate to large DAX tables it takes much more time than in M. And if I were you, I wouldn't even try to calculate tables of the same cardinality as the fact table through DAX.

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D