mysql - 在SQL中计算事件之间的时间范围

Question

我是一个菜鸟，正在尝试编写一个 Sql 来计算下表中不同开始日期之间的时间范围。

 ID         StartDate
202151080   3/27/2014 0:00
202151080   5/16/2014 0:00
202151080   10/27/2014 0:00

我的预期输出是

 ID         StartDate        interval
202151080   3/27/2014 0:00    0
202151080   5/16/2014 0:00    50
202151080   10/27/2014 0:00   164

我可以提出静态..如下所示..我正在努力计算与阅读表的差异。

SELECT id, datediff(dd,'2014-03-27 00:00:00','2014-05-16 00:00:00');

感谢您的宝贵时间。

Answer 1

您可以为此使用相关子查询:

SELECT ID, StartDate,
       COALESCE(DATEDIFF(StartDate, 
                        (SELECT StartDate
                         FROM mytable AS t2
                         WHERE t2.ID = t1.ID AND t2.StartDate < t1.StartDate
                         ORDER BY StartDate DESC LIMIT 1)), 0) AS `interval`
FROM mytable AS t1                             
ORDER BY StartDate

Demo here