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CREATE TABLE timetable (
`id` INTEGER,
`operation_date_time` VARCHAR(19),
`operation` VARCHAR(5)
);
INSERT INTO timetable
(`id`, `operation_date_time`, `operation`)
VALUES
('1', '2000-01-01 06:30:45', 'START'),
('2', '2000-01-01 07:45:00', 'STOP'),
('3', '2000-01-01 08:18:12', 'START'),
('4', '2000-01-01 11:23:58', 'STOP'),
('5', '2000-01-01 15:45:01', 'START'),
('6', '2000-01-01 19:01:33', 'STOP');
SELECT
MIN(id) id
,MIN(`operation_date_time`) `operation_date_time`
,MAX(diff) duration
FROM
(SELECT
id
, IF(`operation` = 'START', 0,TIME_TO_SEC(TIMEDIFF(`operation_date_time`, @datetime))) diff
,IF(`operation` = 'START', @count := @count + 1,@count := @count) groupby
,@datetime := `operation_date_time` `operation_date_time`
FROM
(SELECT * FROM timetable ORDER by `operation_date_time` ASC) t1, (SELECT @datetime := NOW()) a,
(SELECT @count := 0) b) t2
GROUP by groupby;
| id | operation_date_time | duration |
|---|---|---|
| 1 | 2000-01-01 06:30:45 | 4455 |
| 3 | 2000-01-01 08:18:12 | 11146 |
| 5 | 2000-01-01 15:45:01 | 11792 |