I have an SSRS report which takes a value in COL2 as a parameter. Values that will be returned in COL2 are unknown at report design time. The available values for this report parameter should be all the possible (DISTINCT) values that are returned in COL2, so the parameter selection area (prompt) in the report should be a dropdownlist. Unfortunately, COL2 returns duplicate values(see my original post for the example), now COL3 is the solution to the problem of duplicates in the parameter prompt dropdownlist(Instead of providing a parameter dropdownlist with 100 duplicate options, if i return distinct values of COL2 AS COL3, and set my parameter source of values to COL3) i can reduce the available parameter options to say 10 instead of 100 duplicate values.

I would have added a different query to retrieve distinct values of COL2 and then set it to be the source of my parameters available values ,but apparently, SSRS 2005 does not support multiple datasets in a single report.

There is possibly a better way way to accomplish this, am not sure and would like to hear your opinion. thanks