+++ /dev/null
-# TODO: make unit tests out of all this
-
-####### multiple table
-
-from sqlalchemy import *
-
-#db = create_engine('sqlite:///', echo=True)
-db = create_engine('postgres://scott:tiger@127.0.0.1/test', echo=True)
-metadata = BoundMetaData(db)
-
-session = create_session()
-
-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
-
-
-people = Table('people', metadata,
- Column('person_id', Integer, primary_key=True),
- Column('name', String(50)),
- Column('type', String(30)))
-
-engineers = Table('engineers', metadata,
- Column('person_id', Integer, ForeignKey('people.person_id'), primary_key=True),
- Column('engineer_info', String(50)),
- )
-
-managers = Table('managers', metadata,
- Column('person_id', Integer, ForeignKey('people.person_id'), primary_key=True),
- Column('manager_data', String(50)),
- )
-
-people_managers = Table('people_managers', metadata,
- Column('person_id', Integer, ForeignKey("people.person_id")),
- Column('manager_id', Integer, ForeignKey("managers.person_id"))
-)
-
-person_join = polymorphic_union( {
- 'engineer':people.join(engineers),
- 'manager':people.join(managers),
- 'person':people.select(people.c.type=='person'),
- }, None, 'pjoin')
-
-
-
-
-person_mapper = mapper(Employee, people, select_table=person_join, polymorphic_on=person_join.c.type, polymorphic_identity='person',
- properties = dict(managers = relation(Manager, secondary=people_managers, lazy=False))
- )
-
-
-
-mapper(Engineer, engineers, inherits=person_mapper, polymorphic_identity='engineer')
-mapper(Manager, managers, inherits=person_mapper, polymorphic_identity='manager')
-
-
-
-def create_some_employees():
- people.create()
- engineers.create()
- managers.create()
- people_managers.create()
- session.save(Manager('Tom', 'knows how to manage things'))
- session.save(Engineer('Kurt', 'knows how to hack'))
- session.flush()
- session.query(Manager).select()
-try:
- create_some_employees()
-finally:
- metadata.drop_all()
-
-
-####### concrete table
-
-from sqlalchemy import *
-
-db = create_engine("sqlite:///:memory:")
-
-metadata = BoundMetaData(db)
-session = create_session()
-
-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
-
-
-managers_table = Table('managers', metadata,
- Column('employee_id', Integer, primary_key=True),
- Column('name', String(50)),
- Column('manager_data', String(50)),
-).create()
-
-engineers_table = Table('engineers', metadata,
- Column('employee_id', Integer, primary_key=True),
- Column('name', String(50)),
- Column('engineer_info', String(50)),
-).create()
-
-
-
-pjoin = polymorphic_union({
- 'manager':managers_table,
- 'engineer':engineers_table
-}, 'type', 'pjoin')
-
-employee_mapper = mapper(Employee, pjoin, polymorphic_on=pjoin.c.type)
-manager_mapper = mapper(Manager, managers_table, inherits=employee_mapper, concrete=True, polymorphic_identity='manager')
-engineer_mapper = mapper(Engineer, engineers_table, inherits=employee_mapper, concrete=True, polymorphic_identity='engineer')
-
-
-
-session.save(Manager('Tom', 'knows how to manage things'))
-session.save(Engineer('Kurt', 'knows how to hack'))
-session.flush()
-
-
-# this gives you [Engineer Kurt knows how to hack, Manager Tom knows how to manage things]
-# as it should be
-session.query(Employee).select()
-
-# this fails
-session.query(Engineer).select()
-
-# this fails
-session.query(Manager).select()
-
-
-############ single table
-from sqlalchemy import *
-
-db = create_engine("sqlite:///:memory:")
-
-metadata = BoundMetaData(db)
-session = create_session()
-
-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')
-
-
-employees_table.create()
-
-session.save(Manager('Tom', 'knows how to manage things'))
-session.save(Engineer('Kurt', 'knows how to hack'))
-session.flush()
-
-
-# this gives you [Engineer Kurt knows how to hack, Manager Tom knows how to manage things]
-# as it should be
-session.query(Employee).select()
-
-# this gives you [Engineer Kurt knows how to hack, Manager Tom knows how to manage things]
-# instead of [Engineer Kurt knows how to hack]
-session.query(Engineer).select()
-
-
-# this gives you [Engineer Kurt knows how to hack, Manager Tom knows how to manage things]
-# instead of [Manager Tom knows how to manage things]
-session.query(Manager).select()