Dax Help

Hi hoopaz68 ,

In the data you provided, the cruno field does not have a unique identifier and cannot be used as a condition for joining tables.
But based on your requirement, you can refer to the following formula:

SelectedCurrencyRate =
CALCULATE (
    MAX ( 'Currency_Table'[rate] ),
    FILTER (
        'Currency_Table',
        'Currency_Table'[cruno] = SELECTEDVALUE ( 'Invoice Table'[cruno] )
            && 'Currency_Table'[currency] = SELECTEDVALUE ( 'Currency_Table'[currency] )
    )
)

ConvertedInvoiceAmount = 
SUMX(
    'Invoice Table',
    'Invoice Table'[inv_amt_usd] * [SelectedCurrencyRate]
)

Best Regards,
Adamk Kong

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