LeetCode（数据库）- 上升的温度

题目链接：​​点击打开链接​​

题目大意：略。

解题思路：考察点对时间函数的使用，有些人上来就是 “w1.recordDate - w2.recordDate = 1”，这样做最后一个用例通不过，因为跨月份呢，一首凉凉送给你

• 解决方案(1)：DATEDIFF 函数
• 解决方案(2)：TIMESTAMPDIFF 函数
• 解决方案(3)：ADDDATE 函数【推荐，性能最佳】

AC 代码

-- 解决方案(1)
SELECT DISTINCT w1.id
FROM Weather w1, Weather w2
WHERE DATEDIFF(w1.recordDate, w2.recordDate) = 1 AND w1.Temperature > w2.Temperature

-- 解决方案(2)
SELECT a.id
FROM Weather AS a CROSS JOIN Weather AS b 
     ON TIMESTAMPDIFF(DAY, a.recordDate, b.recordDate) = -1
WHERE a.Temperature > b.Temperature;

-- 解决方案(3)
SELECT a.id 
    FROM Weather a JOIN Weather b 
    ON (a.recorddate = ADDDATE(b.recorddate, INTERVAL 1 DAY))
WHERE a.temperature > b.temperature