Django: get unique object list from QuerySet

Question

I have the following (simplified) models in my Django app:

class Color(models.Model):     name = models.CharField(max_length=10)  class Item(models.Model):     name = models.CharField(max_length=200)     color = models.ForeignKey(Color, blank=True, null=True)  class Favorite(models.Model):     user = models.ForeignKey(User)     item = models.ForeignKey(Item) 

I'm currently getting all the items I need using the following query:

favorites = Favorite.objects.filter(user=request.user) 

How can I get all the distinct colors for the items in that QuerySet?

I need the a list of the actual color objects, not just the color ids, which I can get using

favorites.values_list('item__color').distinct 

Answer 1

If I understand you correctly, the following should do the trick:

favorites = Favorite.objects.filter(user=request.user) color_ids = favorites.values_list('item__color', flat=True).distinct() colors = Color.objects.filter(id__in=color_ids) 

There has to be a cleaner way than that though.

Edit: A much cleaner solution:

colors = Color.objects.filter(item__favorite__user=request.user).distinct()