SQLAlchemy InvalidRequestError When Using Composite Foreign Keys

My table relationships in SQLAlchemy have gotten quite complex, and now I'm stuck at this error no matter how I configure my relationship. I'm a bit new to SQLAlchemy so I'm not su

Solution 1:

After a lot of searching I finally found a really simple answer in this answer to another question.

All I did was add 'inherit_condition': (id == Node.id) to the mapper in the classes that inherit from Node so that it looked like this:

__mapper_args__ = {'polymorphic_identity': 'Information',
                   'inherit_condition': (id == Node.id)}

And it works perfectly.