MySQL查询时，查询结果如何按照where in数组排序

MySQL查询时，查询结果如何按照where in数组排序

在查询中，MySQL默认是order by id asc排序的，但有时候需要按照where in 的数组顺序排序，比如where in的id查询数组为[922,106,104,103],正常情况查询出来的结果顺序为[103,104,106,922],这可能不是我们想要的结果，

我们期望查出来的结果顺序与where in的顺序一致，这里介绍两个方式：

1.使用find_in_set函数:

select * from table where id in (922,106,104,103) order by find_in_set(id,'922,106,104,103');

2.使用order by field

select * from table where id in (922,106,104,103) order by field(id,922,106,104,103);

下面是在tp5中的实现过程

 $path = '103-104-106-922';
 $arr = explode('-',$path);
 dump($arr);
 $new_arr = array_reverse($arr);
 dump($new_arr);
 $new_arr1 = implode(',',$new_arr);
 dump($new_arr1);
 $list = Db::name('member')
     ->where('id','in',$new_arr1)
     ->where('type',2)
     ->field('id,type')
     //->order("find_in_set(id,$new_arr1)")
     ->order("field(id,$new_arr1)")
     ->select();
 dump($list);die;

查询结果如下所示，可见实现了按照where in 数组顺序进行排序了

 array(4) {
   [0] => string(3) "103"
   [1] => string(3) "104"
   [2] => string(3) "106"
   [3] => string(3) "922"
 }
 array(4) {
   [0] => string(3) "922"
   [1] => string(3) "106"
   [2] => string(3) "104"
   [3] => string(3) "103"
 }
 string(15) "922,106,104,103"
 array(4) {
   [0] => array(2) {
     ["id"] => int(922)
     ["type"] => int(2)
   }
   [1] => array(2) {
     ["id"] => int(106)
     ["type"] => int(2)
   }
   [2] => array(2) {
     ["id"] => int(104)
     ["type"] => int(2)
   }
   [3] => array(2) {
     ["id"] => int(103)
     ["type"] => int(2)
   }
 }