SQLAlchemy Things

If this appears (may differ a bit)

 AttributeError: 'int' object has no attribute '_sa_instance_state'

then the variabel, in this case an integer should have been an ORM object.

This happens moostly with one-to-many or many-to-many relationships. Make sure your date for the relationship is an ORM object

 session.query(FoobarModel).filter(FoobarModel.id == foobar_id).update({'name': 'New Foobar Name!'})

Since update() belongs to Query, and filter() does return a Query object, this will work.

As for looping over your properties and assigning them by name, you could do this with setattr and a dict, like this:

 foobar = session.query(FoobarModel).get(foobar_id)

 props = {'name': 'my new name'}

 for key, value in props.items():
     setattr(foobar, key, value)

 session.commit()
 session.flush()