I am using python 3.3 and sqlalchemy 0.8.2 I am trying to define a self-referential many-to-many relationship for a class where the primary key is provided by a mixin. Defining the primary directly in the class works. Using the mixin does not.
I would be grateful for any suggestions or pointers to relevant documentation. Below is an example showing my problem. As given the example works. Uncommenting the line "#id = ..." in 'Base' and commenting out the corresponding line in 'A' breaks the example. Is there any way to define the primary key in Base and getting the 'requires' relation to work? ----------------------------------- from sqlalchemy import Column, Integer, String, DateTime, Table, ForeignKey,create_engine from sqlalchemy.ext.declarative import declarative_base,declared_attr from sqlalchemy.orm import sessionmaker, relationship, backref class Base(object): #id = Column(Integer, primary_key=True) pass Base = declarative_base(cls=Base) association_table = Table('association', Base.metadata, Column('prerequisite', Integer, ForeignKey('a.id')), Column('dependency', Integer, ForeignKey('a.id'))) class A(Base): __tablename__ = "a" id = Column(Integer, primary_key=True) requires = relationship("A", secondary = association_table, primaryjoin=(id==association_table.c.prerequisite), secondaryjoin=(id==association_table.c.dependency), backref = backref("required_by")) if __name__ == "__main__": engine = create_engine('sqlite:///:memory:', echo=False) Session = sessionmaker(bind=engine) session = Session() Base.metadata.create_all(engine) T=A() U=A() session.add(T) session.add(U) T.requires.append(U) session.commit() print("T",T.id,T.requires,T.required_by) print("U",U.id,U.requires,U.required_by) -- You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To unsubscribe from this group and stop receiving emails from it, send an email to sqlalchemy+unsubscr...@googlegroups.com. To post to this group, send email to sqlalchemy@googlegroups.com. Visit this group at http://groups.google.com/group/sqlalchemy. For more options, visit https://groups.google.com/groups/opt_out.