的MySQL通过

Question

与多阶选择，所以我得到这个表：

 
+----+---------------------+-----+----------------+ 
| ID | WHEN    | OFF | (other..stuff) | 
+----+---------------------+-----+----------------+ 
| 1 | 2012-09-17 17:00:00 | 0 | anything1  | 
| 2 | 2012-09-17 18:00:00 | 0 | anything2  | 
| 3 | 2012-08-31 21:00:00 | 1 | blabla321  | 
| 4 | 2012-08-31 18:30:00 | 1 | blab32121  | 
+----+---------------------+-----+----------------+ 

我想选择所有的密钥，但：

• 通过时ASC与关闭= 0应该是为了钥匙，他们应该是 显示的第一
• 键与关= 1应该是为了通过时DESC，他们应该之后显示 （末尾）

我想是这样的：

(SELECT * FROM `table` WHERE `off` = 0 ORDER BY `when` ASC) 
UNION 
(SELECT * FROM `table` WHERE `off` = 1 ORDER BY `when` DESC) 

但它不工作。

同时检查： http://i.imgur.com/81Hzq.jpg

Answer 1

select * 
from `table` 
order by `off`, 
    case `off` 
     when 0 then timestampdiff(second, current_timestamp, `when`) 
     when 1 then timestampdiff(second, `when`, current_timestamp) 
    end 

Answer 2

SELECT * 
FROM table 
ORDER BY CASE WHEN off = 0 THEN `when` END ASC, 
     CASE WHEN off = 1 THEN `when` END DESC 

Answer 3

试试这个：

(SELECT * FROM table WHERE off = 0 ORDER BY `when` ASC) 
UNION 
(SELECT * FROM table WHERE off = 1 ORDER BY `when` DESC); 

我认为，当是一个关键字，必须加引号。