Book.objects.annotate(s_count=Count('sequences')).filter(s_count=0)
These are books, that doesn't belong to any sequence. And with one query (though quite heavy query).
2011/5/1 А. Р. <4d876b82@gmail.com>
That's right. But if we have a book that doesn't belong to any sequence,
bs will be *empty*.
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 django-users+unsubscribe@googlegroups.com.
For more options, visit this group at http://groups.google.com/group/django-users?hl=en.
No comments:
Post a Comment