在我的应用程序中,我想建立以下层次结构:
class BaseCadastralObject(Base):
abstract__ = True
cadastral_region = Column(Integer, primary_key=True, index=True)
cadastral_district = Column(Integer, primary_key=True, index=True)
cadastral_object = Column(Integer, primary_key=True, index=True)
这些字段组合一个主键。在
A有一个子类,例如:
^{pr2}$我还有一个表,它应该与以下对象相关(多对多):
class Parameter(Base):
__tablename__ == 'parameters'
parent_cadastral_region = Column(Integer, nullable=False)
parent_cadastral_district = Column(Integer, nullable=False)
parent_cadastral_object = Column(Integer, nullable=False)
parent_building = relationship(BaseCadastralObject, backref='parameters')
^^^^^^^^^^^^^^^^^^^
__table_args__ = (ForeignKeyConstraint(
[parent_cadastral_region, parent_cadastral_district, parent_cadastral_object],
[BaseCadastralObject.cadastral_region, BaseCadastralObject.cadastral_district, BaseCadastralObject.cadastral_object]),
{}
)
我应该能够做到以下几点:
b = Building(...)
parameters = b.parameters
但是我得到了不同的错误例如这个:
sqlalchemy.orm.exc.UnmappedClassError: Class 'app.models.BaseCadastralObject' is not mapped
目前没有回答
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