Source: https://leetcode.com/problems/rising-temperature/#/description
Description:
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 | +----+
Solution:
select w1.Id Id from Weather w1, Weather w2 where datediff(w1.Date,w2.Date)=1 and w1.Temperature>w2.Temperature
197. Rising Temperature (Easy)
原文：http://www.cnblogs.com/sixu/p/6884984.html