如何在mysql中显示剩余/补充日期?
例如,在我的表中有2列,一个快照为
from_date>14-06-2014 and to_date<01-07-2014
会给出这个输出:
From date || To_date
15-06-2014 || 20-06-2014
23-06-2014 || 27-06-2014
29-06-2014 || 30-06-2014
我希望能够显示我们有差距且没有记录的日期,如下所示:
2 //21-06-2014 - 23-06-2014
1 //28-06-2014
这可能吗? 谢谢
答案 0 :(得分:3)
沿着这些方向:
drop table if exists dates;
create table dates (d_from date, d_to date);
insert into dates values
('2014-06-15' , '2014-06-20'),
('2014-06-23' , '2014-06-27' ),
('2014-06-29' , '2014-06-30' );
select low.d_to, high.d_from, to_days(high.d_from) - to_days(low.d_to) - 1 as gap
from dates low, dates high
where high.d_from = (select min(d_from) from dates where d_from > low.d_to)
;
这意味着:在相邻的结束/开始日期将表连接到自身并计算差异。
+------------+------------+------+
| d_to | d_from | gap |
+------------+------------+------+
| 2014-06-20 | 2014-06-23 | 2 |
| 2014-06-27 | 2014-06-29 | 1 |
+------------+------------+------+