如何为django中的一对一字段赋值

Question

我刚刚开始学习 Django 并尝试使用 manage.py shell 为我的模型中的一对一字段赋值。我尝试这样做，但不确定为什么不将值分配给 Author.address

author1 = Author.objects.get(first_name="Sam")
addr1 = Address.objects.get(post_code="12345")
author1.address = addr1

我错过了什么步骤吗？

class Author(models.Model):
    first_name = models.CharField(max_length=100)
    last_name = models.CharField(max_length=100)
    address = models.OneToOneField(Address, on_delete=models.CASCADE, null=True)

    def full_name(self):
        return f"{self.first_name} {self.last_name}"

    def __str__(self):
        return self.full_name()


class Address(models.Model):
    street = models.CharField(max_length=80)
    postal_code = models.CharField(max_length=5)
    city = models.CharField(max_length=50)

    def __str__(self):
        return f"{self.street}"

谢谢

Answer 1

您应该在分配后保存模型

author1 = Author.objects.get(first_name="Sam")
addr1 = Address.objects.get(post_code="12345")
author1.address = addr1
author1.save()

您还可以使用 update 方法更新一对一关系

addr1 = Address.objects.get(post_code="12345")
Author.objects.filter(first_name="Sam").update(address=addr1)

Answer 2

3种方法可用这是例子。

found = User.objects.get(email=obj.email) if not obj.email is None else None
if found and obj.user is None:

        #method 1found = User.objects.get(email=obj.email) if not obj.email is None else None
if found and obj.user is None:
    #method 1
    Profile.objects.filter(pk=obj.id).update(user=found)  
        
    #method 2
    obj.user = found                  
    obj.save(update_fields=['user'])  
        
    #method 3
    with connection.cursor() as cursor:
        cursor.execute("UPDATE users_profile SET user_id = %s WHERE id = %s", ( found.id, obj.id ) )

如何为django中的一对一字段赋值

How to assign value to one-to-one field in django

django

django-models