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Young Kraken
Young Kraken

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197. 上升的温度

197. 上升的温度

SQL架构
表 Weather

+---------------+---------+
| Column Name   | Type    |
+---------------+---------+
| id            | int     |
| recordDate    | date    |
| temperature   | int     |
+---------------+---------+
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id 是这个表的主键
该表包含特定日期的温度信息

编写一个 SQL 查询,来查找与之前(昨天的)日期相比温度更高的所有日期的 id 。

返回结果 不要求顺序 。

查询结果格式如下例:

Weather
+----+------------+-------------+
| id | recordDate | Temperature |
+----+------------+-------------+
| 1  | 2015-01-01 | 10          |
| 2  | 2015-01-02 | 25          |
| 3  | 2015-01-03 | 20          |
| 4  | 2015-01-04 | 30          |
+----+------------+-------------+

Result table:
+----+
| id |
+----+
| 2  |
| 4  |
+----+
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2015-01-02 的温度比前一天高(10 -> 25)
2015-01-04 的温度比前一天高(20 -> 30)

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Young Kraken
SELECT
    w2.id AS 'Id'
FROM
    Weather w1 RIGHT JOIN
    Weather w2 ON DATEDIFF(w2.recordDate, w1.recordDate) = 1
WHERE w2.Temperature > w1.Temperature
;
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