I'm trying to wire up Django to a pre-existing Postgres database that makes heavy use of schemas and am not having any luck. Anyone have experience with this? Should I skip Django's ORM and use SQLAlchemy?
Any advice would be appreciated...
This will work fine until you need to do a cross schema join; at which point you will need to write SQL.
It looks like support is slated for Django 1.1 (maybe) see http://code.djangoproject.com/ticket/6148
That should at least point you in the right direction.
I have a suspicion, though, that (like many things people commonly claim Django's ORM can't do) it is possible to come at this through lesser-known/lesser-considered features. Off the top of my head I can think of two approaches.
In either case, I suspect the key thing to do is write a subclass of django.db.models.sql.query.Query which properly applies schema information when constructing the SQL (Query.get_from_clause() is probably the place to start).
Given the Query class implementing the proper behavior, the two approaches I'd look at are:
1. If schema information is only important for some models but not others, a manager class with an overridden get_query_set() (which returns a QuerySet initialized with an instance of the schema-aware Query) can be applied to the relevant models.
2. If schema information needs to be applied to all models, a subclass of the database backend can have its attribute uses_custom_query_class set True, and then the backend's query_class() method will be called to obtain the default Query class used for all queries from that backend.
Down the road, maybe somebody who really needs this feature will step up during the 1.2 feature-proposal window and work up the necessary bits to have Django do this natively.
And to anyone who does not care about a fancy admin interface, I'd serious recommend Pylons.