On Nov 24, 3:11 pm, Conor <[email protected]> wrote:
> Here is one way you can define your secondary table and ListNode:
>
> class ListNode(Node):
> __mapper_args__ = {'polymorphic_identity': 'list'}
> __tablename__ = 'nodes_list'
>
> id = Column(Integer, ForeignKey('nodes.id'), primary_key=True)
> contents = relation(
> 'ListNodeContents',
> backref='list_node',
> cascade='all,delete-orphan',
> collection_class=ordering_list('position'),
> order_by=lambda: [ListNodeContents.position],
> primaryjoin=lambda: (
> ListNodeContents.list_node_id == ListNode.__table__.c.id))
> nodes = association_proxy(
> 'contents',
> 'node',
> creator=lambda node: ListNodeContents(node=node))
>
Conor - thanks very much for such a detailed answer. If I can impose
on your time for a couple of clarifications, I'd appreciate it.
1) backref='list_node' generates "KeyError: list_node" - I thought
perhaps it should be 'nodes_list' but that generated the same error.
What should backref be?
2) collection_class=ordering_list('position') seems to cause
"AttributeError: 'NoteNode' object has no attribute 'position'". Seems
like that should be referring to the position over in
ListNodeContents; I tried 'ListNodeContents.position' with the same
failure.
As you can tell, I'm sort of feeling around in the dark here. When I
get SQLA stuff to work, it always seems simple in retrospect, and I'm
hoping the same thing happens here. Thanks for any additional help
you can provide!
--
You received this message because you are subscribed to the Google Groups
"sqlalchemy" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to
[email protected].
For more options, visit this group at
http://groups.google.com/group/sqlalchemy?hl=en.
