Thanks Michael.
The question is: how can I use that trick as a relation?
I can do:
session.query(Node).outerjoin(Node.right_nodes)
and
session.query(Node).outerjoin(Node.left_nodes)
but not
session.query(Node).outerjoin(Node.all_nodes)
and that is what I'm looking for. I mean the relation() functionality.
Is there some way to accomplish that?
Thanks again!
Adolfo
On Monday, August 20, 2012 5:35:51 PM UTC-5, Michael Bayer wrote:
>
>
> On Aug 20, 2012, at 6:07 PM, adolfo wrote:
>
> I have a Self-Referential Many-to-Many Relationship situation where the
>
> right_nodes = relationship("Node",
> secondary=node_to_node,
> primaryjoin=id==node_to_node.c.left_node_id,
> secondaryjoin=id==node_to_node.c.right_node_id,
> backref="left_nodes"
>
>
> works fine.
> The problem:
> I need a "related nodes" relationship, which, in one expression, returns
> all related nodes, both left nodes and right nodes, excluding the given
> node itself.
> Is that possible using the RELATIONSHIP construct?
>
>
> this is the "my friends and people who I'm friends with" query and the
> recipe is....well I guess I didn't put it up anywhere yet, the idea is to
> use a @property:
>
> class MyClass(Base):
> # ...
>
> @property
> def all_nodes(self):
> return self.left_nodes + self.right_nodes
>
> to do this in SQL only requires a UNION in a subquery. If you really
> wanted that I can work it out, it's more burdensome but if you have a
> specific query style in mind it could be useful.
>
>
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