Flagging Non-consecutive overlapping dates

digitalPlay You can use the following DAX formula to flag rows that have clashing date ranges against the rest of the dates for a specific location:

Clash = 
VAR CurrentRowEndDate = [End Date]
VAR CurrentRowStartDate = [Start Date]
VAR CurrentRowLocation = [Location]
VAR OverlappingDays = 
    CALCULATE(
        MAX([End Date] - [Start Date] + 1),
        FILTER(
            'Table',
            [Location] = CurrentRowLocation &&
            [Start Date] <= CurrentRowEndDate &&
            [End Date] >= CurrentRowStartDate &&
            [ID] <> EARLIER([ID])
        )
    )
RETURN
    IF(OverlappingDays <= 0, "No Clash", "Clash")

Please note that this formula assumes that the date columns are formatted as dates in your table. If they are not, you may need to adjust the formula accordingly.

 Let me know if this works for you. @ me in replies, or I'll lose your thread!!!  
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