Hm... Again I think I have answered this question already.
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. <4d876...@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+unsubscr...@googlegroups.com.
For more options, visit this group at
http://groups.google.com/group/django-users?hl=en.
