mysql - 计算mysql中所有先前条目的总时间总和

Question

嘿，我必须根据hr_temp_id我的表结构来计算表中所有先前条目的时间

play_id | hr_temp_id  |  min_id    |    
29      | 43          |  00:00:10  |    
30      | 43          |  00:02:00  |    
31      | 43          |  00:00:10  |    
32      | 44          |  00:00:10  |    
33      | 44          |  00:03:15  |   

我试过类似的东西

select r.min_id, (select sum(r2.min_id) from ciam_playlist_template r2 
where r2.min_id <= r.min_id) as cumesum from ciam_playlist_template r 
where r.hr_temp_id=43

我得到了这样的结果

00:00:10 | 10
00:02:00 | 210
00:00:10 | 10

预期结果

00:00:10
00:02:10
00:02:20
00:00:10
00:03:25

有什么建议吗？

Answer 1

DROP TABLE IF EXISTS my_table;

CREATE TABLE my_table
(play_id SERIAL PRIMARY KEY
,hr_temp_id  INT NOT NULL
,min_id TIME NOT NULL
);

INSERT INTO my_table VALUES
(29,43,'00:00:10'),
(30,43,'00:02:00'),
(31,43,'00:00:10'),
(32,44,'00:00:10'),
(33,44,'00:03:15');

SELECT x.*
     , SEC_TO_TIME(SUM(TIME_TO_SEC(y.min_id))) running 
  FROM my_table x 
  JOIN my_table y 
    ON y.hr_temp_id = x.hr_temp_id 
   AND y.play_id <= x.play_id 
 GROUP 
    BY x.play_id;
+---------+------------+----------+----------+
| play_id | hr_temp_id | min_id   | running  |
+---------+------------+----------+----------+
|      29 |         43 | 00:00:10 | 00:00:10 |
|      30 |         43 | 00:02:00 | 00:02:10 |
|      31 |         43 | 00:00:10 | 00:02:20 |
|      32 |         44 | 00:00:10 | 00:00:10 |
|      33 |         44 | 00:03:15 | 00:03:25 |
+---------+------------+----------+----------+

……或者……

SELECT x.*
     , SEC_TO_TIME(CASE WHEN @prev = hr_temp_id THEN @i:= @i+TIME_TO_SEC(min_id) ELSE @i:=TIME_TO_SEC(min_id) END) running
     , @prev := hr_temp_id prev 
  FROM my_table x
     , (SELECT @prev:=null,@i:=0) vars 
  ORDER 
     BY hr_temp_id
      , play_id;