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author | Mike Bayer <mike_mp@zzzcomputing.com> | 2010-01-19 00:53:12 +0000 |
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committer | Mike Bayer <mike_mp@zzzcomputing.com> | 2010-01-19 00:53:12 +0000 |
commit | 40f8aadd582776524d3b98da1f577c2fc95619e7 (patch) | |
tree | 753eec3802734f397953976824a252bb60829189 /examples/inheritance/concrete.py | |
parent | 56fe538cc7d81ce264fc6504feb1ead5e17d0f55 (diff) | |
download | sqlalchemy-40f8aadd582776524d3b98da1f577c2fc95619e7.tar.gz |
- mega example cleanup
- added READMEs to all examples in each __init__.py and added to sphinx documentation
- added versioning example
- removed vertical/vertical.py, the dictlikes are more straightforward
Diffstat (limited to 'examples/inheritance/concrete.py')
-rw-r--r-- | examples/inheritance/concrete.py | 66 |
1 files changed, 66 insertions, 0 deletions
diff --git a/examples/inheritance/concrete.py b/examples/inheritance/concrete.py new file mode 100644 index 000000000..c50513b55 --- /dev/null +++ b/examples/inheritance/concrete.py @@ -0,0 +1,66 @@ +from sqlalchemy import create_engine, MetaData, Table, Column, Integer, String +from sqlalchemy.orm import mapper, create_session, polymorphic_union + +metadata = MetaData() + +managers_table = Table('managers', metadata, + Column('employee_id', Integer, primary_key=True), + Column('name', String(50)), + Column('manager_data', String(40)) +) + +engineers_table = Table('engineers', metadata, + Column('employee_id', Integer, primary_key=True), + Column('name', String(50)), + Column('engineer_info', String(40)) +) + +engine = create_engine('sqlite:///', echo=True) +metadata.create_all(engine) + + +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 + + +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 = create_session(bind=engine) + +m1 = Manager("pointy haired boss", "manager1") +e1 = Engineer("wally", "engineer1") +e2 = Engineer("dilbert", "engineer2") + +session.add(m1) +session.add(e1) +session.add(e2) +session.flush() + +employees = session.query(Employee) +print [e for e in employees] + |