我的解决方案有问题，我找到了以下示例：

(SELECT COUNT(*) FROM person AS b    
WHERE b.group = a.group AND b.age >= a.age) <= 2    
ORDER BY a.group ASC,a.age DESC

（来自：Get top n records for each group of grouped results）

但是我需要在一个旧列的基础上创建一个新列，所以我需要进行一些计算，当我尝试添加更多列时，我会收到一条错误消息。 如果我只是添加满足感，就可以了，例如：

(SELECT COUNT(*) FROM person AS b   
WHERE b.group = a.group AND b.age*100 >= a.age*100) <= 2   
ORDER BY a.group ASC,a.age DESC   

但是当我尝试重命名新列时，AS过多。

我也尝试使用UNION ALL，但是我的SQLite对（）不满意。这根本不适合我：

(   
  select *     
  from mytable    
  where `year` = 2012   
  order by score*100/50 AS percent desc   
  LIMIT 2   
)   
UNION ALL   
(   
  select *   
  from mytable    
  where `year` = 2013   
  order by score*100/50 AS percent desc   
  LIMIT 2   
)   

  

“结果：靠近”（“：语法错误
  在第1行：
  （“

即使我在（）之前执行SELECT和FROM，也收到错误消息。

select * from mytable   
(where `year` = 2012   
  order by score*100/50 AS percent desc   
  LIMIT 2)   

UNION ALL   

select * from mytable    
(where `year` = 2013   
  order by score*100/50 AS percent desc   
  LIMIT 2)   

  

“ WHERE”附近：语法错误

可以请人解释一下为什么吗？

编辑

这里是数据。

| Person | Year  | Score |   
+--------+-------+-------+
| Bob    | 2013  | 32    |   
| Jill   | 2012  | 34    |   
| Shawn  | 2012  | 42    |   
| Jake   | 2012  | 29    |   
| Paul   | 2013  | 36    |   
| Laura  | 2013  | 39    |

所需结果集：

| Person | Year  | Percent |    
+--------+-------+---------+   
| Shawn  | 2012  | 84      |   
| Jill   | 2012  | 68      |   
| Laura  | 2013  | 78      |   
| Paul   | 2013  | 72      |   
+--------+-------+---------+

其中百分比=得分* 100/50