Is it possible to have 2 report parameters set the same actual parameter? For example, the user should either be able to type in an ID, or select it from a dropdown list - for the query to then take that id and run the proc for that id.
One parameter will be displayed just once. So it should be either textbox or dropdown.
But you can create Param_1 for ID, Param_2 for dropdown list and hidden Param_3 with Value=IIF(Parameters!Param_2.Value = nothing, Parameters!Param_1.Value, Parameters!Param_2.Value)