Finding value between dates

Hi jakub_klocek ,

Is the result in your screenshot the result you want? I have test by your data and code. I think it works well if you build a calculated column.

Order Table:

Price(2) Table:

Add a calcualted column in Order Table.

VK Neu = 
CALCULATE (
    SUM ( 'Price(2)'[Old price] ),
    FILTER (
        'Price(2)',
        'Price(2)'[Old from] <= 'Order'[DateNew]
            && 'Price(2)'[New from] >= 'Order'[DateNew]
            && 'Price(2)'[Product] = 'Order'[Product]
    )
)

Output:

Best Regards,
Rico Zhou

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