👀 Views: 252 💬 Answers: 1 📅 Created: 2025-06-12

django django-models queryset Python

I recently switched to I'm experiencing issues with a custom manager that I created for a Django model. The model `Order` has a foreign key to a `Customer` model, and I'm trying to implement a method in the manager to dynamically filter orders based on a customer's status. However, when I call this method, it raises a `RelatedObjectDoesNotExist` behavior. Here’s the relevant code: ```python class Customer(models.Model): name = models.CharField(max_length=100) status = models.CharField(max_length=50) class OrderQuerySet(models.QuerySet): def for_active_customers(self): return self.filter(customer__status='active') class OrderManager(models.Manager): def get_queryset(self): return OrderQuerySet(self.model, using=self._db) def for_active_customers(self): return self.get_queryset().for_active_customers() class Order(models.Model): customer = models.ForeignKey(Customer, on_delete=models.CASCADE) total_price = models.DecimalField(max_digits=10, decimal_places=2) created_at = models.DateTimeField(auto_now_add=True) objects = OrderManager() ``` When I try to call `Order.objects.for_active_customers()` in the Django shell, I get the following behavior: ``` RelatedObjectDoesNotExist: Customer has no related Order. ``` I've double-checked that there are active customers in the database. The question seems to stem from how the query is constructed, but I'm not sure how to address it. I've also tried using `select_related` to optimize the query, but it didn't help. Is there something I’m missing in the way I’m structuring the manager or queryset? Any advice would be appreciated! This is part of a larger web app I'm building. Has anyone else encountered this?