Django，在自类中的多对多关系中，如何在ORM方面互相引用? [英] Django, in many to many relationship within the self class, how do I reference each other in terms of ORM?

问题描述

class User(models.Model):
    name = models.CharField(max_length=100)
    age = models.IntegerField()
    gender = models.IntegerField()
    email = models.CharField(max_length=100)
    password = models.CharField(max_length=255)
    following = models.ManyToManyField("self", related_name='followers')
    objects = UserManager()
    def __repr__(self):
        return "User: {0}".format(self.name)

在我的模型用户"中，用户可以彼此跟随.

In my model, User, users can follow and followed by each other.

我可以由此找到用户关注的人

I can find who the user is following by this:

user1 = User.objects.get(id=1)
following = user1.following.all()

但是，我不知道如何找到用户的关注对象.

However, I can't figure out how to find whom the user is followed by.

我尝试过:

user1.followers.all()

因为它是我模型中以下字段中的related_name.

since it is the related_name in the following field in my model.

有人可以教我该怎么做吗?

Can anybody please teach me how to do this?

非常感谢您.

推荐答案

您应传递从文档中

当Django处理此模型时，它会确定自己具有一个ManyToManyField，因此，它不会向User类添加followers属性.相反，假定ManyToManyField是对称的–也就是说，如果我是您的follower，那么您就是我的follower.

When Django processes this model, it identifies that it has a ManyToManyField on itself, and as a result, it doesn’t add a followers attribute to the User class. Instead, the ManyToManyField is assumed to be symmetrical – that is, if I am your follower, then you are my follower.

如果不想与self建立多对多关系，请将symmetrical设置为False .这将迫使Django为反向关系添加描述符，从而允许ManyToManyField关系是非对称的.

If you do not want symmetry in many-to-many relationships with self, set symmetrical to False. This will force Django to add the descriptor for the reverse relationship, allowing ManyToManyField relationships to be non-symmetrical.

在您的情况下:

class User(models.Model):
    # ...
    following = models.ManyToManyField('self', related_name='followers', symmetrical=False)
    # ...

然后在您的views.py中，您都可以访问以下内容:

Then in your views.py you can access both:

following = user.following.all()
followers = user.followers.all()

自从现在以来，与self的关系是不对称的.

Since now the relationship with self is non-symmetrical.

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