With loader criteria and baked query cache

[Tomas Pavlovsky]

Hello Mike, 

class X()

   id: id: int = Column( Integer, primary_key=True)

   a_id:int = Column(Integer, ForeignKey("A.id"))

subq = select(A_rel_B).join(B).order(B.size).limit(10)

class A()

   id: id: int = Column( Integer, primary_key=True)

   bs = relationship(B, viewonly=True, secondary=subq, uselist=False,primaryjoin=and_(A.id == subq.c.a_id))

class B()

   id: id: int = Column( Integer, primary_key=True)

   size= Column( Integer)

class A_rel_B()

  a_id: :int = Column(Integer, ForeignKey("A.id"))

  b_id: :int = Column(Integer, ForeignKey("B.id"))

 x: int 

q = select(X).options(

   selectinload(A).options(joinedload(A.bs)),

with_loader_criteria(A_rel_B, func.fn(A_rel_B.b_id, x).is_(True))

)

When i add with_loader_criteria(A_rel_B, func.fn(A_rel_B.b_id, x).is_(True)), then x value is cached and don't change. It is ok?

Thanks

[Mike Bayer]

i dont think with_loader_criteria ever expected the target entity to be part of "secondary" in a relationship().  I have no idea what that would do and I'm surprised it works at all.

I would try instead to map from A->A_rel_B->B explicitly and use two relationships for this join.

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