計算上最後一行的總持續時間在MySQL

Question

我有這樣的MySQL查詢：

SELECT CONCAT(u.lastname, ', ', u.firstname) AS Name, start.timestamp start, end.timestamp end, timediff(end.timestamp, start.timestamp) duration 
    from user u, user_group ug, (
    select *, (
     select event_id from event L2 where L2.timestamp>L1.timestamp and L2.user_bannerid=L1.user_bannerid order by timestamp limit 1 
    ) stop_id from event L1 
) start join event end on end.event_id=start.stop_id 
where start.status='In' and end.status='Out' and u.user_bannerid = start.user_bannerid and ug.user_bannerid = u.user_bannerid and ug.group_id = start.group_id 

它顯示是這樣的：

+----------------------------------------------------+---------------+ 
| Name | start    | end     | duration  |  
+----------------------------------------------------+---------------+ 
| User | 2011-11-24 02:12:05 | 2011-11-24 02:12:20 | 00:00:15  |  
| User | 2011-11-28 21:46:54 | 2011-11-28 21:53:01 | 00:06:17  | 
+----------------------------------------------------+---------------+ 

但我想最後一排顯示總持續時間數如下：

+----------------------------------------------------+---------------+ 
| Name | start    | end     | duration  |  
+----------------------------------------------------+---------------+ 
| User | 2011-11-24 02:12:05 | 2011-11-24 02:12:20 | 00:00:15  |  
| User | 2011-11-28 21:46:54 | 2011-11-28 21:53:01 | 00:06:17  | 
|  |      |      | 00:06:32  | 
+----------------------------------------------------+---------------+ 

有人可以幫我修改查詢，以顯示下一個持續時間的總和行？

Answer 1

我不是超級驕傲這個答案的，但它應該工作：

SELECT 0 as is_total, CONCAT(u.lastname, ', ', u.firstname) AS Name, start.timestamp start, end.timestamp end, timediff(end.timestamp, start.timestamp) duration 
    from user u, user_group ug, (
    select *, (
     select event_id from event L2 where L2.timestamp>L1.timestamp and L2.user_bannerid=L1.user_bannerid order by timestamp limit 1 
    ) stop_id from event L1 
) start join event end on end.event_id=start.stop_id 
where start.status='In' and end.status='Out' and u.user_bannerid = start.user_bannerid and ug.user_bannerid = u.user_bannerid and ug.group_id = start.group_id 

UNION 
SELECT 1, null, null, null, sum(duration) 
FROM 
(
    SELECT CONCAT(u.lastname, ', ', u.firstname) AS Name, start.timestamp start, end.timestamp end, timediff(end.timestamp, start.timestamp) duration 
     from user u, user_group ug, (
     select *, (
      select event_id from event L2 where L2.timestamp>L1.timestamp and L2.user_bannerid=L1.user_bannerid order by timestamp limit 1 
     ) stop_id from event L1 
    ) start join event end on end.event_id=start.stop_id 
    where start.status='In' and end.status='Out' and u.user_bannerid = start.user_bannerid and ug.user_bannerid = u.user_bannerid and ug.group_id = start.group_id 

) total 
ORDER BY is_total 

Answer 2

試一下這個效果：

mysql> select *, timediff(end, start) as diff, sec_to_time(SUM(timediff(end,start))) as sum FROM timet GROUP BY start WITH ROLLUP; 

+---------------------+---------------------+-------+----------+----------+ 
| start    | end     | g  | diff  | sum  | 
+---------------------+---------------------+-------+----------+----------+ 
| 2011-11-28 23:00:51 | 2011-11-28 23:00:56 | 0.678 | 00:00:05 | 00:00:05 | 
| 2011-11-28 23:00:52 | 2011-11-28 23:00:57 | f  | 00:00:05 | 00:00:05 | 
| 2011-11-28 23:00:53 | 2011-11-28 23:00:58 | 0.948 | 00:00:03 | 00:00:05 | 
| 2011-11-28 23:00:58 | 2011-11-28 23:01:01 | 0.153 | 00:00:03 | 00:00:03 | 
| NULL    | 2011-11-28 23:01:01 | 0.153 | NULL  | 00:00:18 | 
+---------------------+---------------------+-------+----------+----------+ 
5 rows in set (0.01 sec) 

MySQL的：
Group by, with rollup

Answer 3

我會理想地將這種邏輯歸入第二個查詢或應用層。

但是試圖破譯你的查詢，盡我的能力，你可以嘗試，看看這樣的事情產生你想要什麼：

SELECT 
    CONCAT(u.lastname, ', ', u.firstname) AS Name, 
    start.timestamp AS start, 
    end.timestamp AS end, 
    TIME(SUM(TIMEDIFF(end.timestamp, start.timestamp))) AS duration 
FROM user AS u 
    INNER JOIN user_group AS ug ON u.user_bannerid = ug.user_bannerid 
    INNER JOIN event AS start ON start.user_bannerid = u.user_bannerid AND start.status='In' AND start.group_id = ug.group_id 
    INNER JOIN event AS end ON end.user_bannerid = u.user_bannerid AND end.status='Out' AND start.event_id = end.event_id 
GROUP BY start.event_id WITH ROLLUP 

http://dev.mysql.com/doc/refman/5.5/en/group-by-modifiers.html

編輯：只見那阿瑪多已回答有類似的解決方案，但覺得我的依然是相關的。