How are you doing the delete? This should delete both.
a = sess.query(Peripheral).filter(Peripheral.label=='some label').one() sess.delete(a) sess.commit() This will not work. a = sess.query(Peripheral).filter(Peripheral.label=='some label').delete() I think the explanation here is that in this case we are creating an explicit SQL delete statement without adding Peripheral instances to the session and so there is no knowledge that a related Actuator exists. Someone else might be able to give a better explanation. -- Mike Conley On Tue, Oct 18, 2011 at 9:03 AM, fribes <fri...@gmail.com> wrote: > Hi all, > > Despite some doc and web digging, I didn't find how to tell sqa to behave > the way I want : > on deletion on Peripheral, also delete in Actuator. > > with the following code, the record in Actuator remains after a deletion, > and a subsequent creation fails with IntegrityError. > > class Peripheral(Base): > __tablename__ = 'peripheral' > id = Column(Integer, primary_key=True) > label = Column(String(20), nullable=False) > > __mapper_args__ = {'polymorphic_on': peripheral_type, > 'polymorphic_identity': 'peripheral'} > > class Actuator(Peripheral): > __tablename__ = 'actuator' > __mapper_args__ = {'polymorphic_identity': 'actuator'} > id = Column(None, ForeignKey('peripheral.id'), primary_key=True) > > duration = Column(Integer) > > Any suggestion ? > > Regards, > > -- > You received this message because you are subscribed to the Google Groups > "sqlalchemy" group. > To post to this group, send email to sqlalchemy@googlegroups.com. > To unsubscribe from this group, send email to > sqlalchemy+unsubscr...@googlegroups.com. > For more options, visit this group at > http://groups.google.com/group/sqlalchemy?hl=en. > -- You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To post to this group, send email to sqlalchemy@googlegroups.com. To unsubscribe from this group, send email to sqlalchemy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en.