小编Rob*_*her的帖子

我正在尝试使用 SQLAlchemy ORM 建立友谊模型。我试图建模的关系是对称的。与 Facebook 类似，如果用户 a 要添加用户 b，则用户 b 必须批准该好友请求。我当前的模型如下。

class User(db.Model):
  __tablename__ = 'User'
  id = db.Column(db.Integer, primary_key=True)
  name = db.Column(db.String(35), unique=False)
  username = db.Column(db.String(25), index=True, unique=True)
  password = db.Column(db.String(35), unique=False)
  email = db.Column(db.String(35), unique=True)
  phone_number = db.Column(db.String(22))

  # define relationships
  requester = db.relationship('Relationship', foreign_keys='Relationship.requesting_user', backref='requester')
  receiver = db.relationship('Relationship', foreign_keys='Relationship.receiving_user', backref='received')

  def __repr__(self):
    return '<User %r>' % (self.username)


class Relationship(db.Model):
  __tablename__ = 'Relationship'
  id = db.Column(db.Integer, primary_key=True)
  requesting_user = db.Column(db.Integer, db.ForeignKey('User.id'))
  receiving_user = db.Column(db.Integer, db.ForeignKey("User.id"))
  status = db.Column(db.Integer) …