How do I manage advanced relationships in SQLAlchemy?

How do I manage advanced relationships in SQLAlchemy?

In SQLAlchemy, you can manage advanced relationships using backrefs, association tables, and hybrid properties. What specific relationship are you trying to implement?

I'm trying to set up a many-to-many relationship with additional attributes.

You can achieve that by creating an association table. This table will hold foreign keys to both related tables and any additional attributes you need.

Can you show me an example of how to define that in code?

Sure! Here's a basic example:

association_table = Table('association', Base.metadata,
    Column('left_id', Integer, ForeignKey('left.id')),
    Column('right_id', Integer, ForeignKey('right.id')),
    Column('extra_attribute', String)
)

class Left(Base):
    __tablename__ = 'left'
    id = Column(Integer, primary_key=True)
    rights = relationship('Right', secondary=association_table)

class Right(Base):
    __tablename__ = 'right'
    id = Column(Integer, primary_key=True)

What if I want to query the additional attributes in the association table?

You can query the association table directly by joining it with the related tables. This way, you can access both the related objects and the additional attributes.