Python Django 2.1.7，整数错误，外键约束失败

我对用户和帖子模型之间的ForeignKey关系有一个问题。或者，在为自定义用户模型创建ForeignKey时，会出现一个错误：

回溯：

File "C:\Users\jack_\.virtualenvs\SNDProject-v81rGQ8f\lib\site-packages\django\db\backends\base\base.py" in _commit
  239.                 return self.connection.commit()

The above exception (FOREIGN KEY constraint failed) was the direct cause of the following exception:

File "C:\Users\jack_\.virtualenvs\SNDProject-v81rGQ8f\lib\site-packages\django\core\handlers\exception.py" in inner
  34.             response = get_response(request)

File "C:\Users\jack_\.virtualenvs\SNDProject-v81rGQ8f\lib\site-packages\django\core\handlers\base.py" in _get_response
  126.                 response = self.process_exception_by_middleware(e, request)

File "C:\Users\jack_\.virtualenvs\SNDProject-v81rGQ8f\lib\site-packages\django\core\handlers\base.py" in _get_response
  124.                 response = wrapped_callback(request, *callback_args, **callback_kwargs)

File "C:\Users\jack_\.virtualenvs\SNDProject-v81rGQ8f\lib\site-packages\django\contrib\admin\options.py" in wrapper
  604.                 return self.admin_site.admin_view(view)(*args, **kwargs)

File "C:\Users\jack_\.virtualenvs\SNDProject-v81rGQ8f\lib\site-packages\django\utils\decorators.py" in _wrapped_view
  142.                     response = view_func(request, *args, **kwargs)

File "C:\Users\jack_\.virtualenvs\SNDProject-v81rGQ8f\lib\site-packages\django\views\decorators\cache.py" in _wrapped_view_func
  44.         response = view_func(request, *args, **kwargs)

File "C:\Users\jack_\.virtualenvs\SNDProject-v81rGQ8f\lib\site-packages\django\contrib\admin\sites.py" in inner
  223.             return view(request, *args, **kwargs)

File "C:\Users\jack_\.virtualenvs\SNDProject-v81rGQ8f\lib\site-packages\django\contrib\admin\options.py" in add_view
  1637.         return self.changeform_view(request, None, form_url, extra_context)

File "C:\Users\jack_\.virtualenvs\SNDProject-v81rGQ8f\lib\site-packages\django\utils\decorators.py" in _wrapper
  45.         return bound_method(*args, **kwargs)

File "C:\Users\jack_\.virtualenvs\SNDProject-v81rGQ8f\lib\site-packages\django\utils\decorators.py" in _wrapped_view
  142.                     response = view_func(request, *args, **kwargs)

File "C:\Users\jack_\.virtualenvs\SNDProject-v81rGQ8f\lib\site-packages\django\contrib\admin\options.py" in changeform_view
  1525.             return self._changeform_view(request, object_id, form_url, extra_context)

File "C:\Users\jack_\.virtualenvs\SNDProject-v81rGQ8f\lib\site-packages\django\db\transaction.py" in __exit__
  212.                         connection.commit()

File "C:\Users\jack_\.virtualenvs\SNDProject-v81rGQ8f\lib\site-packages\django\db\backends\base\base.py" in commit
  261.         self._commit()

File "C:\Users\jack_\.virtualenvs\SNDProject-v81rGQ8f\lib\site-packages\django\db\backends\base\base.py" in _commit
  239.                 return self.connection.commit()

File "C:\Users\jack_\.virtualenvs\SNDProject-v81rGQ8f\lib\site-packages\django\db\utils.py" in __exit__
  89.                 raise dj_exc_value.with_traceback(traceback) from exc_value

File "C:\Users\jack_\.virtualenvs\SNDProject-v81rGQ8f\lib\site-packages\django\db\backends\base\base.py" in _commit
  239.                 return self.connection.commit()

Exception Type: IntegrityError at /admin/auth_pp/posts/add/
Exception Value: FOREIGN KEY constraint failed

错误页：

我为代码中可能存在的缺陷和语法错误提前道歉。提前谢谢你

编辑：

---

错误只发生在admin中，在shell中有效

OneToOneField表示一个用户只有一个post，一个post只有一个用户 这将添加唯一约束。 您需要使用外键（是的，您没有使用它）

---

OneToOneField表示一个用户只有一个帖子，而一个帖子只有一个用户 这将添加唯一约束。 您需要使用外键（是的，您没有使用它）

---

请您提供错误，以及当前行为和预期的错误？您希望这样用户只能发表一篇文章还是多篇文章？正如Whodini所暗示的，您的

作者

字段是一个

OnToneField

。这意味着它将有一个外键约束，确保用户和帖子之间最多只能有一对一的关系。我猜您已经创建了多个帖子，当您尝试添加此模型时，它失败了，因为您的

default=1

将导致多个帖子与一个用户关联。我尝试更改

default=None

，但结果保持不变。请提供错误，对于当前行为和预期行为？您希望这样做，以便用户只能拥有一篇帖子还是多篇帖子？正如Whodini所暗示的，您的

作者

字段是一个

ontonefield

。这意味着它将有一个外键约束，确保用户和帖子之间最多只能有一对一的关系。我猜您已经创建了多个帖子，当您尝试添加此模型时，它失败是因为您的

default=1

将导致多个帖子与一个用户关联。我试图更改

default=None

，但当我将

OneToOneField

替换为

ForeignKey

错误时，结果保持不变，无法避免指定ForeignKey构造函数的删除参数或看到错误文档中的示例即使我将

OneToOneField

替换为

ForeignKey

错误也无法避免为ForeignKey的构造函数指定delete参数或查看文档中的示例

#CustomUserModel
class Usr(AbstractBaseUser):
    username = models.CharField(max_length=30, validators=[
    RegexValidator(
            regex=USERNAME_REGEX,
            message='Username must be alphanumeric or numbers',
            code='invalid_username'
        )
    ], unique=True)

    objects = UsrManager()

    is_active = models.BooleanField(default=True)
    is_admin = models.BooleanField(default=False)
    is_staff = models.BooleanField(default=False)
    is_superuser = models.BooleanField(default=False)


    def has_perm(self, perm, obj=None):
    # Simplest possible answer: Yes, always
    return True

    def has_module_perms(self, app_label):  
    # Simplest possible answer: Yes, always
    return True

    USERNAME_FIELD = 'username'
    REQUIRED_FIELDS = []

#Model with ForeignKey 
class Posts(models.Model):
    title = models.CharField(max_length=50, unique=True)
    text = models.CharField(max_length=300)
    author = models.OneToOneField(get_user_model() ... default=1, swappable=True, related_query_name='post', db_constraint=True,      related_name='posts', on_delete=models.CASCADE)

author = models.ForeignKey(...)