Django @property calculating a model field: FieldError: Cannot resolve keyword
django, python
Solution
Solved by using `sorted()`
I was using a query with order_by() to call rating. order_by() is at the database level and doesnt know about my property. Soultion, use Python to sort instead:
sorted(Restaurant.objects.filter(category=category[0]), key=lambda x: x.rating, reverse=True)[:5]
If you encounter a similar error check through your views for anything that might be calling the property. Properties will no longer work at the datatbase level.
Problem
I'm following the method used by @Yauhen Yakimovich in this question: do properties work on django model fields? To have a model field that is a calculation of a different model. The Problem: ``` FieldError: Cannot resolve keyword 'rating' into field. Choices are: _rating ``` The `rating` model field inst correctly hidden and overridden by my `rating` property causing an error when I try to access it. My model: ``` class Restaurant(models.Model): ... ... @property def rating(self): from django.db.models import Avg return Review.objects.filter(restaurant=self.id).aggregate(Avg('rating'))['rating__avg'] ``` Model in Yauhen's answer: ``` class MyModel(models.Model): __foo = models.CharField(max_length = 20, db_column='foo') bar = models.CharField(max_length = 20) @property def foo(self): if self.bar: return self.bar else: return self.__foo @foo.setter def foo(self, value): self.__foo = value ``` Any ideas on how to correctly hid the `rating` field and define the `@property` technique?