+------+------------+------------+
| id | start_date | end_date |
+------+------------+------------+
| 1 | 2019-01-01 | 2019-01-12 |
| 1 | 2019-01-10 | 2019-01-27 |
| 1 | 2019-01-13 | 2019-01-15 |
| 1 | 2019-01-18 | 2019-01-25 |
| 1 | 2019-02-10 | 2019-02-15 |
| 2 | 2019-01-10 | 2019-01-15 |
+------+------------+------------+
如何在 mysql(8.X) 中合并重叠间隔并得到以下结果?
+------+------------+------------+
| id | start_date | end_date |
+------+------------+------------+
| 1 | 2019-01-01 | 2019-01-27 |
| 1 | 2019-02-10 | 2019-02-15 |
| 2 | 2019-01-10 | 2019-01-15 |
+------+------------+------------+
下面是mysql中可以使用的创建表的命令=>
insert into interval_dates(id, start_date, end_date) values(1, '2019-01-01', '2019-01-12');
insert into interval_dates(id, start_date, end_date) values(1, '2019-01-10', '2019-01-27');
insert into interval_dates(id, start_date, end_date) values(1, '2019-01-13', '2019-01-15');
insert into interval_dates(id, start_date, end_date) values(1, '2019-01-18', '2019-01-25');
insert into interval_dates(id, start_date, end_date) values(1, '2019-02-10', '2019-02-15');
insert into interval_dates(id, start_date, end_date) values(2, '2019-01-10', '2019-01-15');
您能否分享任何优雅的解决方案,无需插入mysql(8.X)中的中间表?
最佳答案
请检查:
SELECT id, start_date, MAX(end_date) end_date
FROM ( SELECT id,
@p_start := CASE WHEN (start_date > @p_end) OR (@p_id < id)
THEN start_date
ELSE @p_start
END start_date,
@p_end := CASE WHEN (end_date > @p_end) OR (@p_id < id)
THEN end_date
ELSE @p_end
END end_date,
@p_id := id
FROM mytable, ( SELECT @p_id := MIN(id)-1,
@p_start := MIN(start_date) - INTERVAL 1 DAY,
@p_end := MIN(start_date) - INTERVAL 1 DAY
FROM mytable ) variables
ORDER BY id, start_date, end_date ) subquery
GROUP BY id, start_date;
fiddle (甚至在 5.6 中也适用)。
我尚未找到产生错误结果的源数据。
关于mysql - 使用mysql重叠间隔,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/59827875/