DAX to Identify earliest date amongst common rows

[SK77]

Hello 

I am trying to create a DAX formula that creates a new collumn that for any duplicate set of ID numbers identifes with 'Yes' the row that has the earliest date and a 'no' for all the others. Example of end result I am after is: 

ID	Date	*New Collumn*
A	01/01/2024	Yes
A	02/01/2024	No
B	01/01/2023	Yes
B	02/01/2023	No
C	01/01/2024	Yes

I appreciate any help!

Thanks 

[Jihwan_Kim]

Hi,

Please check the below picture and the attached pbix file.

INDEX function (DAX) - DAX | Microsoft Learn

Expected result CC =
VAR _earliest =
    MINX (
        INDEX (
            1,
            Data,
            ORDERBY ( Data[Date], ASC ),
            ,
            PARTITIONBY ( Data[ID] ),
            MATCHBY ( Data[ID], Data[Date] )
        ),
        Data[Date]
    )
RETURN
    IF ( Data[Date] = _earliest, "Yes", "No" )

[SK77]

Thank you! nearly there. But is there away to have this work with duplicates? Whereby any duplicate is identified with a 'yes'. Example:

ID	Date	Expected result CC
A	1/1/24	Yes
A	1/1/24	Yes
A	1/1/25	No
B	1/2/23	Yes
B	1/2/24	No
C	1/1/24	Yes

[Jihwan_Kim · Accepted solution]

Hi,

I am not sure if I understood your question correctly, but please check the below picture and the attached pbix file.

Expected result CC = 
VAR _earliest =
    MINX (
        INDEX (
            1,
            SUMMARIZE(Data, Data[ID], Data[Date]),
            ORDERBY ( Data[Date], ASC ),
            ,
            PARTITIONBY ( Data[ID] ),
            MATCHBY ( Data[ID], Data[Date] )
        ),
        Data[Date]
    )
RETURN
    IF ( Data[Date] = _earliest, "Yes", "No" )

[SK77]

Perfect! thank you very much