601. 体育馆的人流量

X 市建了一个新的体育馆，每日人流量信息被记录在这三列信息中：序号 (id)、日期 (date)、 人流量 (people)。

请编写一个查询语句，找出高峰期时段，要求连续三天及以上，并且每天人流量均不少于100。

例如，表 stadium：

+------+------------+-----------+
| id   | date       | people    |
+------+------------+-----------+
| 1    | 2017-01-01 | 10        |
| 2    | 2017-01-02 | 109       |
| 3    | 2017-01-03 | 150       |
| 4    | 2017-01-04 | 99        |
| 5    | 2017-01-05 | 145       |
| 6    | 2017-01-06 | 1455      |
| 7    | 2017-01-07 | 199       |
| 8    | 2017-01-08 | 188       |
+------+------------+-----------+

对于上面的示例数据，输出为：

+------+------------+-----------+
| id   | date       | people    |
+------+------------+-----------+
| 5    | 2017-01-05 | 145       |
| 6    | 2017-01-06 | 1455      |
| 7    | 2017-01-07 | 199       |
| 8    | 2017-01-08 | 188       |
+------+------------+-----------+

Note:
每天只有一行记录，日期随着 id 的增加而增加。

 

# Write your MySQL query statement below
select * from (
	select a.* from stadium a 
		join stadium b on b.id = a.id + 1
		join stadium c on c.id = a.id + 2
	where a.people >= 100 and b.people >= 100 and c.people >= 100
	union
	select b.* from stadium a 
		join stadium b on b.id = a.id + 1
		join stadium c on c.id = a.id + 2
	where a.people >= 100 and b.people >= 100 and c.people >= 100
	union
	select c.* from stadium a 
		join stadium b on b.id = a.id + 1
		join stadium c on c.id = a.id + 2
	where a.people >= 100 and b.people >= 100 and c.people >= 100
)a order by id;

 

转载于:https://www.cnblogs.com/ccXgc/p/9334710.html