I have a fairly complicated django app going that uses the same app models across multiple databases. Querysets have the .using() function which makes this fairly easy to deal with (except contenttypes…) but I ran into a situation today where I needed to go backwards from a model and find out which database it came from. I didn’t find any answers online or in irc, so I dug into some source and tracked down the _state.db attribute on models. Here is an example:
results = Model.objects.using('test_database').all()
Hopefully you find this quickly if you have the same question I had.