Laravel中3个模型之间的关系

Question

我正在尝试在 Laravel 5.6 中建立 3 个模型之间的关系

这是我的桌子

部门

• 身份证
• 姓名

主题

• 身份证
• 姓名

教师

• 身份证
• 姓名

教

• id_teacher
• id_department
• id_subject

所有表之间的关系是多对多的。

• 老师可以在很多部门教很多科目

• 科属多学科

• 主题属于多个部门

如何在教师、部门和学科模型中建立这些关系？

Answer 1

你可以试试这样的：

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

class Department extends Model
{
    /**
     * The teachs that belong to the department.
     */
    public function teachs()
    {
        return $this->belongsToMany('App\Teach', 'teach_department', 'department_id', 'teach_id');
    }
}

class Subject extends Model
{
    /**
     * The teachs that belong to the subject.
     */
    public function teachs()
    {
        return $this->belongsToMany('App\Teach', 'teach_subject', 'subject_id', 'teach_id');
    }
}

class Teacher extends Model
{
    /**
     * The teachs that belong to the teacher.
     */
    public function teachs()
    {
        return $this->belongsToMany('App\Teach', 'teach_teacher', 'teacher_id', 'teach_id');
    }
}

class Teach extends Model
{
    /**
     * The departments that belong to the teach.
     */
    public function departments()
    {
        return $this->belongsToMany('App\Department', 'teach_department', 'teach_id', 'department_id');
    }

    /**
     * The subjects that belong to the teach.
     */
    public function subjects()
    {
        return $this->belongsToMany('App\Subject', 'teach_subject', 'teach_id', 'subject_id');
    }

    /**
     * The teachers that belong to the teach.
     */
    public function teachers()
    {
        return $this->belongsToMany('App\Teacher', 'teach_teacher', 'teach_id', 'teacher_id');
    }
}