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daxcalculated-columnsmeasure

DAX code change from calculated column to a measure

I have a fact table with settlement_date, product_id, service_id, location_id, and ticket_id and srv_adjusted_earning columns.

I have determined the DAX query to generate a calculated column that sums the srv_adjusted_earning column over the date range: settlement date and settlement date - 27 days (i.e. a 4 week window) as:

=CALCULATE(
    SUM(factService[SRV_ADJUSTED_EARNING]),
    DATESBETWEEN
    (
        factService[SETTLEMENT_DATE],
        DATEADD(factService[SETTLEMENT_DATE], -27, DAY), 
        factService[SETTLEMENT_DATE]
    ),
    FILTER(factService, factService[PRO_ID] = EARLIER(factService[PRO_ID])),
    FILTER(factService, factService[SER_ID] = EARLIER(factService[SER_ID])),
    FILTER(factService, factService[LOC_ID_SELLING] = 
        EARLIER(factService[LOC_ID_SELLING])),
    FILTER(factService, factService[TIS_ID] = EARLIER(factService[TIS_ID]))
)

I am trying to convert this DAX calculated column to a measure and I tried the following:

blob:=CALCULATE
(
    SUM(factService[SRV_ADJUSTED_EARNING]),
    DATESBETWEEN
    (
        factService[SETTLEMENT_DATE], 
        DATEADD(factService[SETTLEMENT_DATE], -27, DAY), 
        factService[SETTLEMENT_DATE]
    ),
    ALLEXCEPT(factService, factService[PRO_ID]),
    ALLEXCEPT(factService, factService[SER_ID]),
    ALLEXCEPT(factService, factService[LOC_ID_SELLING]),
    ALLEXCEPT(factService, factService[TIS_ID])
)

But I get: Error: Calculation error in measure 'factService'[blob]: A single value for column 'SETTLEMENT_DATE' in table 'factService' cannot be determined. This can happen when a measure formula refers to a column that contains many values without specifying an aggregation such as min, max, count, or sum to get a single result.

Anybody know how I fix this?

Solution

  • As the error mentions, the issue is with factService[SETTLEMENT_DATE]. In the measure, there is no row context so that it knows which date you are talking about, so you need to specify it somehow. I'd suggest using a variable along these lines:

    blob :=
VAR SettleDate = MAX ( factService[SETTLEMENT_DATE] )
RETURN
    CALCULATE (
        SUM ( factService[SRV_ADJUSTED_EARNING] ),
        DATESBETWEEN (
            factService[SETTLEMENT_DATE],
            SettleDate - 27,
            SettleDate
        ),
        ALLEXCEPT (
            factService,
            factService[PRO_ID],
            factService[SER_ID],
            factService[LOC_ID_SELLING],
            factService[TIS_ID]
        )
    )

    Here the variable picks the maximal settlement date in the current filter context. If that's not exactly what you need, adjust the definition accordingly.