Rising Temperature [MySQL]

题目

Given a Weather table, write a SQL query to find all dates' Ids with higher temperature compared to its previous (yesterday's) dates.

+---------+------------+------------------+
| Id(INT) | Date(DATE) | Temperature(INT) |
+---------+------------+------------------+
|       1 | 2015-01-01 |               10 |
|       2 | 2015-01-02 |               25 |
|       3 | 2015-01-03 |               20 |
|       4 | 2015-01-04 |               30 |
+---------+------------+------------------+

For example, return the following Ids for the above Weather table:

+----+
| Id |
+----+
|  2 |
|  4 |
+----+

 

代码

select w1.Id from Weather w1, Weather w2 where TO_DAYS(w1.Date)-TO_DAYS(w2.Date)=1 and w1.Temperature > w2.Temperature;

 

posted @ 2015-08-07 10:27  Hygeia  阅读(184)  评论(0编辑  收藏  举报