millerdev wrote:
>
>> > Thanks a lot for the tips on how to approach this problem. That's
>> > exactly what I needed.
>>
>> in 0.4 you'd get it off the impl (0.5 too, this is just uglier API):
>
> Excellent! Here's what I came up with as an initial solution:
>
> def poly_load(parent, collection, path):
> def itersiblings(parent, path):
> def iteritems(items, attr):
> for item in items:
> for child in getattr(item, attr):
> yield child
> items = [parent]
> while path:
> items = iteritems(items, path.pop(0))
> return items
> path = path.split(".")
> assert len(path) % 2 == 0, "path must contain an even number of
> elements"
> mid = len(path) / 2
> gparent = parent
> for attr in path[:mid]:
> gparent = getattr(gparent, attr)
> session = sqlalchemy.orm.session.object_session(parent)
> backref = getattr(type(parent), collection).property.backref.key
> itemclass = getattr(type(parent),
> collection).property.mapper.class_
> qry = session.query(itemclass) \
> .join([backref] + path[:mid]) \
> .filter(type(gparent).table.c.id == gparent.id)
> groups = defaultdict(list)
> for item in qry:
> groups[getattr(item, backref).id].append(item)
> impl = getattr(type(parent), collection).impl
> for sibling in itersiblings(gparent, path[mid:]):
> if sibling.id in groups:
> impl.set_committed_value(sibling._state, groups.get
> (sibling.id))
>
do i see correctly the implementation relies upon the presence of a
backref ? thats an example of a perfectly fine restriction that is not
good enough for core ;) .
--~--~---------~--~----~------------~-------~--~----~
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
-~----------~----~----~----~------~----~------~--~---
