Nodejs序列化多个自我关联

Question

我正在尝试实现多个自我关联：

const StudentGuardian = db.define(
  'student_guardians',
  {
    id: {
      allowNull: false,
      autoIncrement: true,
      primaryKey: true,
      type: Sequelize.INTEGER
    }
  },
  { timestamps: false }
);

User.belongsToMany(User, {
  as: 'firstGuardian',
  through: StudentGuardian,
  foreignKey: 'firstGuardianId'
});
User.belongsToMany(User, {
  as: 'secondGuardian',
  through: StudentGuardian,
  foreignKey: 'secondGuardianId'
});
User.belongsToMany(User, {
  as: 'student',
  through: StudentGuardian,
  foreignKey: 'studentId'
});

这是我要插入到student_guardians表中的代码：

const guardians = {
    firstGuardianId: body.firstGuardianId,
    secondGuardianId: body.secondGuardianId
  };
 const newStudent = await User.create({ ...newUser }, { transaction: t });
      guardians.studentId = newStudent.id;
      await StudentGuardian.create(guardians, { transaction: t });

这是生成的查询：

INSERT INTO "student_guardians" ("id","secondGuardianId","studentId") VALUES (DEFAULT,$1,$2) RETURNING *;

我不知道为什么它不插入 firstGuardianId ，而仅插入 secondGuardianId 和 studentId 。 有人有主意吗？谢谢