Hi,
I wish to have a two-levels inheritance, but I don't know how to proceed.
The docs says that "only one discriminator column or SQL expression may be
configured for the entire inheritance hierarchy".
I tried with this example (mixing joined and single inheritances) :
class Person(Base):
__tablename__ = 'person'
id = Column(Integer, primary_key=True)
type = Column(String(50), nullable=False)
name = Column(String(50))
__mapper_args__ = {
'polymorphic_identity': 'person',
'polymorphic_on': type
}
class Manager(Person):
__tablename__ = 'manager'
id = Column(ForeignKey('person.id'), primary_key=True)
manager_name = Column(String(30))
__mapper_args__ = {
'polymorphic_identity': 'manager',
}
class EngineerBase(Person):
__tablename__ = 'engineer'
id = Column(ForeignKey('person.id'), primary_key=True)
engineer_name = Column(String(30))
class EngineerType1(EngineerBase):
__mapper_args__ = {
'polymorphic_identity': 'engineer_t1',
}
class EngineerType2(EngineerBase):
__mapper_args__ = {
'polymorphic_identity': 'engineer_t2',
}
It seems to work, but it this correct ?
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