leetcode-601-Human-Traffic-of-Stadium

描述


X city built a new stadium, each day many people visit it and the stats are saved as these columns: id, date, people

Please write a query to display the records which have 3 or more consecutive rows and the amount of people more than 100(inclusive).

For example, the table stadium:

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+------+------------+-----------+
| 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 |
+------+------------+-----------+

For the sample data above, the output is:

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

分析


找出人数超过100的,连续的日期超过三天的数据。

解决方案(MySQL)


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# Write your MySQL query statement below
SELECT s1.id as id, s1.date as date, s1.people as people from stadium as s1, stadium as s2, stadium as s3 WHERE
((s1.id = s2.id-1 AND s2.id = s3.id-1) OR
(s2.id = s1.id-1 AND s1.id = s3.id-1) OR
(s2.id = s3.id-1 AND s3.id = s1.id-1)) AND
s1.people>=100 AND s2.people>=100 AND s3.people>=100
GROUP BY s1.id;

题目来源