Data Model - online mode creation - CountDistinct aggregation

Hi,

I have the following requirement to build a Data Model in online mode with BI Publisher 11.1.1.6.8.

 

Creating the Element By Expression: CountDistinct the number of rows of a column OVER PARTITION BY another column.

 

Example:

Column 1           Column 2        calculated item: countdistinct(column2, column1)

    A                        1                                      3

    A                        2                                      3

    A                        3                                      3

    B                        2                                      2

    B                        2                                      2

    B                        3                                      2

    B                        3                                      2

 

I tried subgrouping within a SQL dataset to aggregate the other column, however the aggregation CountDistinct is not available.

Would one have been successful in builing such a function with BIP in online mode and could explain how to proceed ?

Regards,

Matthieu Miquel