MySQL多表联查之ThinkPHP中的实现

创建两个表如图：

sp_user表：

sp_dept表：

目的：通过sp_user的dept_id查询所属部门即sp_dept中的name。

原生sq方法一：select t1.*,t2.name as deptname from sp_user as t1,sp_dept as t2 where t1.dept_id = t2.id;

原生sq方法二：select t1.*,t2.name as deptname from sp_user as t1 left join sp_dept as t2 on t1.dept_id = t2.id;

结果相同：

对应thinkphp中，则也有两种方法table和join如下：

 1 //多表联查(table)
 2     public function test18() {
 3         //实例化模型
 4         $model = m();
 5         //查询
 6         $result = $model->field('t1.*, t2.name as deptname')->table('sp_user as t1, sp_dept as t2')->where('t1.dept_id = t2.id')->select();
 7         dump($result);
 8     }
 9     //多表联查(join)
10     public function test19() {
11         //实例化模型
12         $model = m('user');
13         //查询
14         $result = $model->field('t1.*, t2.name as deptname')->alias('t1')->join('left join sp_dept as t2 on t1.dept_id = t2.id')->select();
15         dump($result);
16     }

测试结果相同：

 

综上：thinkphp进行多表联查可通过table方法和join方法分别实现，测试环境thinkphp3.2.3，表前缀sp_