我有一个用户表和约会表.在约会表中,我有两个用户ID(customer_id,staff_id).我想检索所有带有客户名称和员工姓名的约会.
users table id name appointments table id staff_id(user_id) customer_id(user_id) datetime
如您所见,我必须使用约会表两次加入users表.
通常我用内连接来做这个.
我们可以使用with()使用Laravel eloquent eager loading来做同样的事情吗？
我们可以这样做：
appointments::with('users' * )->get();?
* Do something here to inner join users table twice,and read user1.name as staff_name,user2.name as customer_name.
这是我需要的最终输出：
appointment_id staff_id staff_name customer_id customer_name datetime
我有另一个问题,以下查询中的第二个参数是什么？
User::with(array(
'post'=> function() use $region {
//what is use $region means? Can you give me an example?
}
));
谢谢！
class T1 extends Eloquent {
protected $table = 't1';
}
class T2 extends Eloquent {
protected $table = 't2';
public function customer()
{
return $this->belongsTo('T1','c_id');//c_id - customer id
}
public function staff()
{
return $this->belongsTo('T1','s_id');//s_id - staff id
}
}
1)使用“with”：
$list = \T2::with('customer')->with('staff')->get();
foreach ($list as $row) {
echo 'ID: '.$row->id.',customer: '.$row->customer->name.',staff: '.$row->staff->name.'<br>';
}
2)加入：
$list = \T2::leftJoin('t1 as customer_table','customer_table.id','=','t2.c_id')
->leftJoin('t1 as staff_table','staff_table.id','t2.s_id')
->select('staff_table.name as staff_name','customer_table.name as customer_name')
->get();
foreach ($list as $row) {
echo 'customer: '.$row->customer_name.',staff: '.$row->staff_name.'<br>';
}
关于第二个问题 – 这是针对子查询的.查看文档：http://laravel.com/docs/eloquent#eager-loading
