Laravel Eloquent渴望加载中：加入同一表格两次

Question

我有一个用户表和约会表。在预约表中，我有两个用户ID（customer_id，staff_id）。我想用客户名称和员工姓名检索所有约会。

users table 
id 
name 

appointments table 
id 
staff_id(user_id) 
customer_id(user_id) 
datetime 

正如你所看到的，我必须用约会表两次加入users表。 通常我会这样做内连接。

我们可以用Laravel雄辩地用（）来加载吗？

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. 

这是最后的输出我需要：

appointment_id 
staff_id 
staff_name 
customer_id 
customer_name 
datetime 

我还有一个问题，什么是在下面的查询第二个参数？

User::with(array(
    'post'=> function() use $region { 
      //what is use $region means? Can you give me an example? 
    } 
)); 

谢谢！

Answer 1

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）利用 “与”：

$list = \T2::with('customer')->with('staff')->get(); 
    foreach ($list as $row) { 
     echo 'ID: '.$row->id.', customer: '.$row->customer->name.', staff: '.$row->staff->name.'<br>'; 
    } 

2）随着加入：

$list = \T2::leftJoin('t1 as customer_table', 'customer_table.id','=','t2.c_id') 
     ->leftJoin('t1 as staff_table', 'staff_table.id','=','t2.s_id') 
     ->select('staff_table.name as staff_name','customer_table.name as customer_name') 
     ->get(); 
foreach ($list as $row) { 
    echo 'customer: '.$row->customer_name.', staff: '.$row->staff_name.'<br>'; 
} 

关于第二个问题 - 这是一个子查询。 Look documentation：http://laravel.com/docs/eloquent#eager-loading