> when was that raised...when defining mappers ? this is all very hard > to follow without an attachment of the full code.
Yes: things diverged a bit from the starting example. Below a self contained test case. It fails fetching classes neither root nor leaf in an inheritance tree. Am i doing something wrong in setting up the mappers? -- Daniele ---- from sqlalchemy import * metadata = BoundMetaData('sqlite://') # Database metadata employees = Table('employees', metadata, Column('person_id', Integer, primary_key=True), Column('name', String(50)), Column('type', String(30))) managers = Table('managers', metadata, Column('person_id', Integer, ForeignKey('employees.person_id'), primary_key=True), Column('manager_data', String(50))) boss = Table('boss', metadata, Column('person_id', Integer, ForeignKey('managers.person_id'), primary_key=True), Column('powers', String(50))) metadata.create_all() # Python classes class Employee(object): pass class Manager(Employee): pass class Boss(Manager): pass # Mapping objects person_join = polymorphic_union({ 'person':employees.select(employees.c.type=='person'), 'manager':employees.join(managers), 'boss':employees.join(managers).join(boss), }, None, 'pjoin') person_mapper = mapper(Employee, employees, select_table=person_join, polymorphic_on=person_join.c.type, polymorphic_identity='person') manager_mapper = mapper(Manager, managers, inherits=person_mapper, polymorphic_identity='manager') mapper(Boss, boss, inherits=manager_mapper, polymorphic_identity='boss') # Testing serialization ses = create_session() for emp in [ Employee(), Manager(), Boss() ]: ses.save(emp) ses.flush() ses.clear() #print ses.query(Employee).select() # this works print ses.query(Manager).select() # this doesn't #print ses.query(Boss).select() # this works too --~--~---------~--~----~------------~-------~--~----~ 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 [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~----------~----~----~----~------~----~------~--~---