class Position(Field):
__tablename__ = 'position'
id = db.Column(db.ForeignKey("field.id"), primary_key=True)
x = Column(db.Numeric(), default=0)
y = Column(db.Numeric(), default=0)
z = Column(db.Numeric(), default=0)
w = Column(db.Numeric(), default=1)
__mapper_args__ = {"polymorphic_identity": "position"}
class Number(Field):
__tablename__ = 'number'
id = Column(db.ForeignKey("field.id"), primary_key=True)
value = Column(db.Numeric())
__mapper_args__ = {"polymorphic_identity": "number"}