My fault, I must have skipped right over that part. It seems that it *does* send pre_delete and post_delete signals, but does not call custom delete methods
On Jun 17, 9:51 am, Daniel Hepper <[EMAIL PROTECTED]> wrote: > > It isn't very clear from that sentence which of the two methods Django > > uses to delete those child records, but looking at the code, it seems > > to be method #2. Since it's using the more-efficient batch delete, no > > custom delete methods are being called, no signals are being sent, > > which is exactly the problem you're having. > > > The solution is to override the delete method (or respond to the > > pre_delete signal), on your *parent* model, in this case > > 'Participant'. That way, when you delete the Participant, you can > > delete all related Data records by hand. > > I had a quick glance at the code and I came to the opposite conclusion. > > A comment [1] in the delete() method in the QuerySet class says: > > "# Collect all the objects to be deleted in this chunk, and all the > # objects that are related to the objects that are to be deleted." > > This collection is then passed to the delete_objects [2] function where > the SQL magic happens and it definitely sends signals. > > Confused as I was, I just tried it. I have a Video model which haa a > VideoHost model as foreign key. I defined a function that prints its > parameter and attached it to the post_delete signal: > > >>> def print_sig(*args,**kwargs): > > ... for x in args: print str(x) > ... for k,v in kwargs.items(): print k,v > > >>> dispatcher.connect(print_sig, signal=signals.post_delete) > > Then I deleted one VideoHost[3]: > > >>> VideoHost.objects.all()[0].delete() > > All related Videos got deleted as well, and signals got sent: > > instance Video 1 on YouTube > signal <object object at 0xb7d8f4a8> > sender <class 'videosite.videos.models.Video'> > instance Video 2 on YouTube > signal <object object at 0xb7d8f4a8> > sender <class 'videosite.videos.models.Video'> > instance Video 3 on YouTube > signal <object object at 0xb7d8f4a8> > sender <class 'videosite.videos.models.Video'> > instance YouTube > signal <object object at 0xb7d8f4a8> > sender <class 'videosite.videos.models.VideoHost'> > > It seems signals are the way to go, or did I miss something? > > Regards, > Daniel > > [1]http://code.djangoproject.com/browser/django/trunk/django/db/models/q... > [2]http://code.djangoproject.com/browser/django/trunk/django/db/models/q... > [3] OMG, I deleted YouTube! :) --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to django-users@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/django-users?hl=en -~----------~----~----~----~------~----~------~--~---
