If you want to have the form dynamically connect to the database or make web service calls, you either need to have the form reader-extended or use the full Acrobat.
An alternative that you could use (this is a very narrow use case) would be to have your server put the data into a form data packet that referenced the form and dynamically serve that up, letting reader do the merge. We can chat more on this on the opff-hand chance that this could fill your need.
