For the most part, you don't need to deal with DBD::* directly, not even to use it. The DBI module figures out which DBD driver to load from the "connect string" given the constructor, &DBI::connect. You rarely need to call driver subs directly, just call DBI methods and let DBI sort it out.

Usually, all you need to do about particular drivers is check whether all the DBI methods you want to use are supported.