601. Human Traffic of Stadium
2018-06-12 本文已影响0人
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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
:
+------+------------+-----------+
| 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:
+------+------------+-----------+
| id | date | people |
+------+------------+-----------+
| 5 | 2017-01-05 | 145 |
| 6 | 2017-01-06 | 1455 |
| 7 | 2017-01-07 | 199 |
| 8 | 2017-01-08 | 188 |
+------+------------+-----------+
Note:
Each day only have one row record, and the dates are increasing with id increasing.
Answer:
select distinct s1.id, s1.date, s1.people
from stadium s1 inner join stadium s2 inner join stadium s3
on ((s2.id=s1.id-1 and s3.id-2=s2.id) or ( s2.id-1=s1.id and s3.id-2=s1.id) or ( s2.id=s1.id-2 and s3.id-1=s2.id))
where s1.people>=100 and s2.people>=100 and s3.people>=100
order by s1.id