#10262: Allow to clear object before deleting to avoid data loss because delete cascade behaviour ------------------------------------------+--------------------------------- Reporter: msaelices | Owner: nobody Status: new | Milestone: Component: Database layer (models, ORM) | Version: 1.0 Keywords: | Stage: Unreviewed Has_patch: 1 | ------------------------------------------+--------------------------------- Imaging a model like this: {{{ #!python class Master(models.Model): name = models.CharField(max_length=100)
class Slave(models.Model): name = models.CharField(max_length=100) master = models.ForeignKey(Master, null=True) }}} And this object creation: {{{ #!python >>> m1 = Master.objects.create(name="master1") >>> s1 = Slave.objects.create(name="slave1", master=m1) >>> m1.delete() # this will also delete s1 }}} Django by default, delete in cascade all related objects... even with {{{null=True}}}. If you want to avoid this, you can do this: {{{ #!python >>> m1.slave_set.clear() >>> m1.delete() }}} This is ok, but it was wonderful if I can change behaviour to not delete cascade. You can think in admin site for example. If you want to delete a Category object you have previously to enter in maybe a hundred objects to set null by hand. I propose a definition like this: {{{ #!python class Slave(models.Model): name = models.CharField(max_length=100) master = models.ForeignKey(Master, null=True, delete_cascade=False) }}} With {{{delete_cascade=False}}} (by default would be {{{True}}}), {{{delete()}}} method will clear this relation previously deletion. I've attached a patch that implements this idea. -- Ticket URL: <http://code.djangoproject.com/ticket/10262> Django <http://code.djangoproject.com/> The Web framework for perfectionists with deadlines. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Django updates" group. To post to this group, send email to django-updates@googlegroups.com To unsubscribe from this group, send email to django-updates+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/django-updates?hl=en -~----------~----~----~----~------~----~------~--~---