Django ValueError: Не удается запросить "instructor": Должен быть экземпляр "User"

При попытке зайти на свою домашнюю страницу я получаю следующую ошибку:

    ValueError at / 
    Cannot query "instructor": Must be "User" instance. 
    Request Method: GET 
    Request URL: http://127.0.0.1:8000/ 
    Django Version: 5.2 
    Exception Type: ValueError 
    Exception Value: Cannot query "instructor": Must be "User" instance. 
    Exception Location: C:\Users\User LENOVO\OneDrive\Bureau\E-Learning\venv\Lib\site- 
    packages\django\db\models\sql\query.py, line 1346, in check_query_object_type 
    Raised during: base.views.Accueille 

class User(AbstractUser):
instructor = models.BooleanField(default=False)
# ... other fields

class Course(models.Model):
title = models.CharField(max_length=255)
description = models.TextField()
instructor = models.ForeignKey(User, on_delete=models.CASCADE, related_name='courses')
# ... other fields
class Home(View):
def get(self, request):
    try:
        courses = Course.objects.select_related('instructor').all()
        # ... rest of the view

The error occurs because one of the Course objects has an invalid instructor reference, most likely pointing to a non-existent user. Django expects the instructor always to be a valid User instance but gets None or something unexpected.

Filter out courses without a valid instructor:
courses = Course.objects.select_related('instructor').filter(instructor__isnull=False)

Вернуться на верх