Timmy Timmy - 11 days ago 6
Python Question

Best way to do enum in Sqlalchemy?

im reading sqlalchemy and i see the code

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), nullable=False)
)

employee_mapper = mapper(Employee, employees_table, \
polymorphic_on=employees_table.c.type, polymorphic_identity='employee')
manager_mapper = mapper(Manager, inherits=employee_mapper, polymorphic_identity='manager')
engineer_mapper = mapper(Engineer, inherits=employee_mapper, polymorphic_identity='engineer')


should i make 'type' an int, with constants in a library? or should i make just make type an enum?

Answer

SQLAlchemy has an Enum type since 0.6: http://docs.sqlalchemy.org/en/latest/core/type_basics.html?highlight=enum#sqlalchemy.types.Enum

Although I would only recommend it's usage if your database has a native enum type. Otherwise I would personally just use an int.