Hi, I'm trying the single table inheritance example (see the attachment) from the 0.2 docs, and it fails with the following traceback:
Traceback (most recent call last): File "single.py", line 37, in ? manager_mapper = mapper(Manager, inherits=employee_mapper, polymorphic_identity='manager') File "f:\lib\python\pyfr\__init__.py", line 49, in mapper File "build\bdist.win32\egg\sqlalchemy\orm\mapper.py", line 139, in __init__ File "build\bdist.win32\egg\sqlalchemy\sql.py", line 39, in join File "build\bdist.win32\egg\sqlalchemy\sql.py", line 1017, in __init__ File "build\bdist.win32\egg\sqlalchemy\sql.py", line 1037, in _match_primaries AttributeError: 'NoneType' object has no attribute 'foreign_keys' ideas ?
from sqlalchemy import * metadata = DynamicMetaData() class Employee(object): def __init__(self, name): self.name = name def __repr__(self): return self.__class__.__name__ + " " + self.name class Manager(Employee): def __init__(self, name, manager_data): self.name = name self.manager_data = manager_data def __repr__(self): return self.__class__.__name__ + " " + self.name + " " + self.manager_data class Engineer(Employee): def __init__(self, name, engineer_info): self.name = name self.engineer_info = engineer_info def __repr__(self): return self.__class__.__name__ + " " + self.name + " " + self.engineer_info employees_table = Table('employees', metadata, Column('employee_id', Integer, primary_key=True), Column('name', String(50)), Column('manager_data', String(50)), Column('engineer_info', String(50)), Column('type', String(20)) ) employee_mapper = mapper(Employee, employees_table, polymorphic_on=employees_table.c.type) manager_mapper = mapper(Manager, inherits=employee_mapper, polymorphic_identity='manager') engineer_mapper = mapper(Engineer, inherits=employee_mapper, polymorphic_identity='engineer') metadata.connect('sqlite://', echo=True)