Finding values from related tables for Dax and Field parameter values not shown

Excellove15 

As for the first part. When we select Category Main (Budget or Target or Nothing)  we pick-up all categories related to selected main. Thus for the Budget or Target list of categories finally applied for filtering is {Unit, Cost}. There is no Carbon in such list, it appears only Main is not filtered.

With first case filtered Parameter table is empty, Carbon is not selectable and result is blank.

In general, for Carbon calculating we need to remove filter context from Category Main.

In case of parameter table we can't remove shadow filter content since internally DAX makes grouping and we can't get content from the column grouped by other column.

As workaround we may modify ShowValues as

VAR SelectedParameter =
    SELECTEDVALUE ( 'Parameter 3'[Category] )
VAR nRows = COUNTROWS('Parameter 3')+0
VAR Result =
    SWITCH (
        SelectedParameter,
        "Units", SUM ( DataInvoice[Units] ),
        "Cost", SUM ( DataInvoice[Cost] ),
        "Carbon", [Carbon tCO2e]
    )
RETURN
    IF(nRows = 0, [Carbon tCO2e], Result )

However, not very reliable from maintenance point of view if we will be modifying parameters configuration.

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