This is bull. I've used straight mysql_* calls, PEAR::MDB2, as well as a custom rolled DB abstraction class before. Personally, I prefered MDB2 because of the portability and ability to do prepared statements (which wasn't available in our version of MySQL and PHP at the time). Changing the few bits of SQL that need changed is far easier than retooling an entire application (i.e. code changes). The other added value is that the developers don't have to relearn the DB functions.