Finding Best Product per Client

Hi PDRTXRA ,

You can try code as below to create calculated columns in 'Client' table. 

First column = 
VAR _ADDCOLUMN =
    ADDCOLUMNS (
        Sales,
        "Rank",
            RANKX (
                FILTER ( Sales, Sales[ClientID] = EARLIER ( Sales[ClientID] ) ),
                Sales[SalesValue],
                ,
                DESC,
                DENSE
            )
    )
RETURN
    MAXX (
        FILTER (
            _ADDCOLUMN,
            AND ( [ClientID] = EARLIER ( Client[ClientID] ), [Rank] = 1 )
        ),
        [ProductName]
    )

Second column = 
VAR _ADDCOLUMN =
    ADDCOLUMNS (
        Sales,
        "Rank",
            RANKX (
                FILTER ( Sales, Sales[ClientID] = EARLIER ( Sales[ClientID] ) ),
                Sales[SalesValue],
                ,
                DESC,
                DENSE
            )
    )
RETURN
    MAXX (
        FILTER (
            _ADDCOLUMN,
            AND ( [ClientID] = EARLIER ( Client[ClientID] ), [Rank] = 2 )
        ),
        [ProductName]
    )

Third column = 
VAR _ADDCOLUMN =
    ADDCOLUMNS (
        Sales,
        "Rank",
            RANKX (
                FILTER ( Sales, Sales[ClientID] = EARLIER ( Sales[ClientID] ) ),
                Sales[SalesValue],
                ,
                DESC,
                DENSE
            )
    )
RETURN
    MAXX (
        FILTER (
            _ADDCOLUMN,
            AND ( [ClientID] = EARLIER ( Client[ClientID] ), [Rank] = 3 )
        ),
        [ProductName]
    )

Result is as below.

Here I create a virtual table in my code, if you don't want to add a rank column in 'Sales' table, you can use the workaround above. Or you can add a rank column firstly in Sales table and then column will be easier.

Rank =
RANKX (
    FILTER ( Sales, Sales[ClientID] = EARLIER ( Sales[ClientID] ) ),
    Sales[SalesValue],
    ,
    DESC,
    DENSE
)

First column 1 =
CALCULATE (
    MAX ( Sales[ProductName] ),
    FILTER (
        Sales,
        AND ( [ClientID] = EARLIER ( Client[ClientID] ), Sales[Rank1] = 1 )
    )
)

Second column and Third column are in the same logic.

Best Regards,
Rico Zhou

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