Thanks Robert! That is so unexpectedly simple - I hadn't realised that I had a query object - or that I could order by the dates like that.
On Feb 24, 8:05 pm, Robert Kluin <[email protected]> wrote: > Brian, > I just re-read your thread more carefully. I think what you want to > know is simply: > reel_frames = reel.frames.order('auto_now_add_prop.order') > > 'frames' on Reel (created by the reference property from Frames) is > just a query object. > > Robert > > On Wed, Feb 24, 2010 at 3:01 PM, Robert Kluin <[email protected]> wrote: > > Alex, > > You can only order by properties on the model itself. If you want > > to order by a property on a referenced model, you need to include it. > > So in your case you might want to add a "reelName" property to Frame, > > then just be sure you handle updating that property when you change > > the name on Reel. > > > Robert > > > On Wed, Feb 24, 2010 at 9:09 AM, Alex <[email protected]> wrote: > >> Hi, > >> Is it possible to do anything with a reference property other than > >> cycle through the referenced objects in whatever order they are > >> returned? For example I have a number of reference properties to > >> instances where the creation date is crucial to how they are > >> subsequently managed. Is there a way to order the result? > > >> class Reel(db.Model): > >> name = db.StringProperty() > > >> class Frame(db.Model): > >> # datetime.datetime.now() when the object is first created. > >> auto_now_add_prop = db.DateTimeProperty(auto_now_add=True) > >> # reference to the one and only reel this frame belong to > >> reel = db.ReferenceProperty(Reel, collection_name='frames') > > >> I would like to order 'reel.frames' depending on the > >> 'auto_now_add_prop' date. Is this the right way to access these > >> instances if date order access is frequent and crucial? > >> The Frame model will have millions of instances so a query there > >> matching for a given Reel instance would be expensive. Ideas/advice/a > >> thread I haven't seen? > > >> Alex > > >> -- > >> You received this message because you are subscribed to the Google Groups > >> "Google App Engine" 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 > >> athttp://groups.google.com/group/google-appengine?hl=en. -- You received this message because you are subscribed to the Google Groups "Google App Engine" 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/google-appengine?hl=en.
