multiple exclude

Question

is there a way to do a query and exclude a list of things instead of calling exclude multiple times?

Answer 1

What's wrong with calling exclude multiple times? Queries are lazy, nothing happens until you try to pull data from it, so there's no downside to using .exclude() more than once.

Answer 2

You can do it pretty easily with the Q object:

from django.db.models import Q

excludes = None
for tag in ignored_tags:
    q = Q(tag=tag)
    excludes = (excludes and (excludes | q)) or q # makes sure excludes is set properly
set_minus_excluded = Foo.objects.exclude(excludes)

You should also be able to do it dynamically with exclude():

qs = Foo.objects.all()
for tag in ignored_tags:
    qs = qs.exclude(tag=tag)

Answer 3

Based on your reply to Ned, it sounds like you just want to exclude a list of tags. So you could just use the in filter:

names_to_exclude = [o.name for o in objects_to_exclude] 
Foo.objects.exclude(name__in=names_to_exclude)

Does that do what you want?