OK will do - please give me a few days...
On Jun 24, 8:43 pm, Carles Gonzalez <carle...@gmail.com> wrote:
> Not to be annoying, but can you post an example?
>
> Just to organize the things in my head...
>
> Thanks again.
>
>
>
> On Fri, Jun 25, 2010 at 2:41 AM, Carles Gonzalez <carle...@gmail.com> wrote:
> > Very interesting!
>
> > I'll try tomorrow.
>
> > Thanks a lot, Dave.
>
> > On Fri, Jun 25, 2010 at 1:21 AM, dlypka <dly...@gmail.com> wrote:
> >> I've done a parent - to - many child GAE / web2py implementation using
> >> SelfReference fields (or you can use Reference as well) using the
> >> technique for adding native GAE fields into a web2py table definition.
>
> >> It gives fantastic retrieval performance because GAE automatically
> >> adds the link from the child back into the parent's reference list
> >> at the time you create each child. When you later query for the
> >> parent, voila GAE retrieves all the child entities along with it in
> >> one backend call!
>
> >> Hopefully this technique is relevant to your application.
>
> >> I also develop some other tricks for inheriting native GAE classes
> >> into your web2py model, though
> >> this is less attractive perhaps now that GAE native properties can be
> >> directly declared in web2py tables.
>
> >> - Dave Lypka.
>
> >> On Jun 21, 10:25 am, Carles Gonzalez <carle...@gmail.com> wrote:
> >>> Hi,
>
> >>> I have developed some applications in web2py, and 2 are running
> >>> currently in gae, but now i have serious problem.
>
> >>> My current project is a social application, and when i design
> >>> (example) the tables to make an user follow the actions other user
> >>> (twitter like) I find that many-to-many relationships in app-engine
> >>> are not easily supported.
>
> >>> From my understanding using the tools present in web2py right i would
> >>> need to do a lot of processing in memory, an that would hurt
> >>> performance greatly.
>
> >>> The pattern proposed by app store developers uses lists and "parent"
> >>> relationship:
>
> >>> class Message(db.Model):
> >>> sender = db.StringProperty()
> >>> body = db.TextProperty()
>
> >>> class MessageIndex(db.Model):
> >>> receivers = db.StringListProperty()
>
> >>> indexes = MessageIndex.all(keys_only = True).filter('receivers = ',
> >>> user_id)
> >>> keys = [k.parent() for k in indexes)
> >>> messages = db.get(keys)
>
> >>> For using that pattern in web2py I would need a method for specifying
> >>> the parent of a model instance. Can I specify that relationship using
> >>> any method I don't know? If not, would it be hard to implement?
>
> >>> Thanks in advance!
