On Feb 27, 12:25 pm, Calvin Spealman <[email protected]> wrote: > On Fri, Feb 27, 2009 at 11:45 AM, Øyvind Saltvik > > Should be doable but you need to filter on a field of the subclass > > being null. > > > SomeModel.objects.filter(somemodelsubclass__somefield=None) , > > somefield cannot be id or pk. > > That is one method I found, but it seems very incorrect to add a field > just for this, with no real data. I was wondering if it would be > appropriate to add to every model subclass a "fake" field or simply to > add to the query API, so that someone could do > SomeModel.objects.filter(somesubclass__isinstance=True). The > hypothetical name here is chosen for obvious reasons. Alternatively, > something aside from filter might be appropriate, like > SomeModel.objects.instancesof(SomeModelSubclass). > > Should I file a ticket? I would like to look at contributing an > implementation of whichever would be favorable, if either would be up > for consideration.
I wrote about something similar on my blog, which lets you filter for instances of a Model which are not actually instances of any children models. The link is at http://sciyoshi.com/blog/2008/aug/07/custom-django-manager-excludes-subclasses/ - might be possible (and probably not too hard) to customize it for your case. Hope that can be of help! --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Django developers" 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/django-developers?hl=en -~----------~----~----~----~------~----~------~--~---
