Skip to main content

关联查询-一对多

info

hasMany(关联模型类名，关联模型外键，当前模型外键)

一、模型中定义规则​

示例：Student.php
<?php
namespace app\models;

use core\base\Model;

class Student extends Model
{
    protected $tables = 'student';

    public function __construct()
    {
        parent::__construct($this->tables);
    }
}
示例：Classroom.php
<?php

namespace app\models;

use core\base\Model;

class Classroom extends Model
{
    protected $tables = 'classroom';

    public function __construct()
    {
        parent::__construct($this->tables);
    }
    
    public function hasManyStudent()
    {
        return $this->hasMany(Student::class, 'cid');
    }
}

二、控制器中调用​

源数据：

图片alt

图片alt

2.1 方法一​

示例
$class = Classroom::find(1);
$data = $class->hasManyStudent();
pd($data);

图片alt

2.2 方法二​

示例
$res = Classroom::with('hasManyStudent')
    ->field('student.id as sid,cname,classroom.id as cid,sname')
    ->where('classroom.id','=',1)
    ->select();
pd($res);

图片alt