Corss posted from stack
overflow<http://stackoverflow.com/questions/15923809/django-queryset-in-operator-fails-on-first-call>
When using the 'in' operator on a queryset, the first time the call is made
it fails.
from django.db import models
class Category(models.Model):
name = models.CharField(max_length=100)
class Project(models.Model):
categories = models.ManyToManyField(Category, related_name='projects')
category_list = Category.objects.prefetch_related('projects')
print category_list # [<Category: Category object>, <Category: Category
object>]print category_list[0] in category_list # Falseprint category_list[0]
in category_list # True
If I remove 'prefetch_related' and use 'all' instead then the problem is
gone, however this uses many more DB calls.
How can I get the correct result first time using prefetch_related?
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