Is there a way to pull parameter values dynamically? For example, I would like to run a proc SQL command, pull distinct values from a database, and then use those values as the values in the parameter.
This question has come up frequently in the forums, so if you search, you will find those other conversations. The short answer is no, there's not a way to populate a list of parameter value choices dynamically, at this time. This feature, of the Enterprise Intelligence Platform, is set to be delivered in the SAS 9.2 time frame with the release of the Platform for 9.2 -- (at least, I believe those are the plans).
If you are asking about setting parameters in EG ONLY (outside the scope of the Enterprise Intelligence Platform), then I believe the answer is still NO.
If you wrote your own .NET or .COM application, you might be able to figure out a way to prompt for dynamic parameter values, but you would be using your custom application to build the list of parameter value choices and not EG or the Enterprise Intelligence client apps in this case.