Treat NULL as '0' in Django model

Question

I use the following bit of code in my Django app:

pictures = gallery.picture_set.annotate( score=models.Sum( \'picturevote__value\' ) ).order_by( \'-score\'          


        

Answer 1

From Django 1.8, there is a Coalesce database function. Your query might look like this:

from django.db.models.functions import Coalesce    

score = self.picturevote_set.aggregate(Coalesce(models.Sum('value'), 0))