Adding one column by removing duplicates in another

Hi Syndicate_Admin ,

Please try to create a measure with below dax formula:

Measure =
VAR _date =
    SELECTEDVALUE ( 'Table'[Date] )
VAR _year =
    YEAR ( _date )
VAR _month =
    MONTH ( _date )
VAR _ws =
    SELECTEDVALUE ( 'Table'[Workshop] )
VAR tmp =
    FILTER (
        ALL ( 'Table' ),
        [Workshop] = _ws
            && YEAR ( [Date] ) = _year
            && MONTH ( [Date] ) = _month
    )
RETURN
    SUMX ( tmp, [Calendar Hour] )

Add a table visual with table fields and measure:

Please refer the attached .pbix file.

Best regards,
Community Support Team_Binbin Yu
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