nearest date match value

Hi, Akbera1 

Based on your description, I created data to reproduce your scenario. The pbix file is attached in the end.

Table:

You may create a calculated column or a measure as below.

Calculated column:
Result Column = 
IF(
    [Date1]=[Date2],
    [Another Date],
    var _diff1 = ABS(TODAY()-[Date1])
    var _diff2 = ABS(TODAY()-[Date2])
    return
    IF(
        MIN(_diff1,_diff2)=_diff1,
        [Date1],
        [Date2]
    )
)

Measure:
Result Measure = 
var _date1 = SELECTEDVALUE('Table'[Date1])
var _date2 = SELECTEDVALUE('Table'[Date2])
return
IF(
    _date1=_date2,
    SELECTEDVALUE('Table'[Another Date]),
    var _diff1 = ABS(TODAY()-_date1)
    var _diff2 = ABS(TODAY()-_date2)
    return
    IF(
        MIN(_diff1,_diff2)=_diff1,
        _date1,
        _date2
    )
)

Result:

Best Regards

Allan

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