Question

星期五快乐所有，我有一些无法分类的东西。我之前曾寻求过支持，发现这是我能做的最好的事情：）因此，我想基于打开和关闭两个日期来计算未清项目的数量。所有数据都将计入t2，日期将从t1开始（该日期存储了大量日期，因此我使用SELECT DISTINCT）

因此，这些表如下：

CREATE TABLE t1
(

ID int (10),
Date1 date);


insert into T1 values 
( 1, '2018-12-17'),
( 2, '2018-12-18'),
( 3, '2018-12-19'),
( 4, '2018-12-19'),
( 5, '2018-12-19'),
( 6, '2018-12-20'),
( 7, '2018-12-20'),
( 8, '2018-12-21'),
( 9, '2018-12-22'),
(10, '2018-12-23'),
(11, '2018-12-24'),
(12, '2018-12-25'),
(13, '2018-12-26'),
(14, '2018-12-27'),
(15, '2018-12-28');

CREATE TABLE t2
(

ID int (10),
Open_Date date,
Close_Date date);


insert into t2 values 
( 1, '2018-12-17', '2018-12-18'),
( 2, '2018-12-18', '2018-12-18'),
( 3, '2018-12-18', '2018-12-18'),
( 4, '2018-12-19', '2018-12-20'),
( 5, '2018-12-19', '2018-12-21'),
( 6, '2018-12-20', '2018-12-22'),
( 7, '2018-12-20', '2018-12-22'),
( 8, '2018-12-21', '2018-12-25'),
( 9, '2018-12-22', '2018-12-26'),
(10, '2018-12-23', '2018-12-27');

这是我想要的结果：

+------------+------------+
| Date       | Count_open | 
+------------+------------+
| 17/12/2018 |          1 | 
| 18/12/2018 |          3 | 
| 19/12/2018 |          2 | 
| 20/12/2018 |          3 | 
| 21/12/2018 |          4 | 
| 22/12/2018 |          4 | 
| 23/12/2018 |          3 | 
| 23/12/2018 |          0 | 
| 25/12/2018 |          0 | 
| 27/12/2018 |          0 | 
| 27/12/2018 |          0 | 
| 28/12/2018 |          0 | 
+------------+------------+

我对代码完全不了解，需要您的帮助。

Answer 1

也许这就是您想要的？

select
  x.Date1 as 'Date',
  count(distinct t2.id) as 'Count_open'
from (select distinct Date1 from t1) x
left join t2 on x.Date1 between t2.Open_Date and t2.Close_Date
group by x.Date1
order by x.Date1

结果：

Date        Count_open
----------  ----------
2018-12-17  1                      
2018-12-18  3                      
2018-12-19  2                      
2018-12-20  4                      
2018-12-21  4                      
2018-12-22  4                      
2018-12-23  3                      
2018-12-24  3                      
2018-12-25  3                      
2018-12-26  2                      
2018-12-27  1                      
2018-12-28  0

MySQL-计算未清项目并从其他表中获取日期

1 个答案: