Automatically add a new column based on user Option

[rsaripa]

Hi,

Can we automatically add a column to the report based on user selection.
Here is the scenario

We have a data item FIELD-A which is primary column in the table. There is another data item FIELD-B which can have multiple values for corresponding values of FIELD-A. We have third data item FIELD-C which always displays the most recent value for each of FIELD-A. Now here is the situation,

We created a Query Subject which contains all the above three data items. The requirement is  when a user tries to create a report using data items FIELD-A, FIELD-B and
a. applies filters on FIELD-B, the report should populate the corresponding values from FIELD-B (This works)
b. but when a user doesn't use any filters on FIELD-B, it should automatically populate FIELD-C. (Is this possible?)

Thanks!