Using Django with PostgreSQL schemas
brutimus: In any situation like this I've been in and tried to attempt django, it's turned out to be a complete failure.  You need an ORM that knows how to construct SQL properly and map existing tables.  Go with your second option: SQLAlchemy.  Use that with SQLSoup (an extension), mapping tables on the fly is a breeze and you can manually tweak your queries to do about anything you need: polymorphism, correlated subqueries, etc.  I have a feeling that if you attempt the Django route, you're going to spend more time wondering "well why the hell doesn't this ORM do _____?"  That's my opinion on the subject.