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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