Map to input rows offers no columns to be used for mapping
I'm struggling to return columns from a data function and map them to the input rows. The input of my data function can be limited by marking so I added a RowId() column. If I specify the output parameter to use the output handler "columns" I was expecting that I can select that RowId() column under "Map to input rows" according to this document. However, the only thing offered in the pull down menu is "[None]". What's the trick to allow selecting a column to be used for mapping?