Question

There is an sqlalchemy object

class Employee(Base):
    __tablename__ = "employee"
    # Columns
    id = Column(Integer, primary_key=True, autoincrement=True)
    representative_id = Column(Integer, ForeignKey('employee.id'))
    parent_id = Column(Integer, ForeignKey('employee.id'))
    affiliate_id = Column(Integer, ForeignKey('employee.id'))

    # Relatonships
    representative = relationship("Employee", ????)
    parent = relationship("Employee", ????)
    affiliate = relationship("Employee", ????)

How to configure the relationships in the right way if an employee can have, 0 or 1 parent, affiliate and representative? Do know these three are different ones. DB – MySQL

Answer 1

I found out how do to it by myself:

class Employee(Base):
    __tablename__ = "employee"
    # Columns
    id = Column(Integer, primary_key=True, autoincrement=True)
    representative_id = Column(Integer, ForeignKey('employee.id'))
    parent_id = Column(Integer, ForeignKey('employee.id'))
    affiliate_id = Column(Integer, ForeignKey('employee.id'))

    # Relatonships
    representative = relationship("Employee", 
                         primaryjoin="Employee.representative_id==Employee.id", 
                         remote_side=[id])
    parent = relationship("Employee",
                         primaryjoin="Employee.parent_id==Employee.id", 
                         remote_side=[id])
    affiliate = relationship("Employee",
                         primaryjoin="Employee.affiliate_id==Employee.id", 
                         remote_side=[id])