【MySQL】【leetcode】 Second Highest Salary解題報告

題目

Write a SQL query to get the second highest salary from the Employee table.

+—-+——–+
| Id | Salary |
+—-+——–+
| 1 | 100 |
| 2 | 200 |
| 3 | 300 |
+—-+——–+
For example, given the above Employee table, the second highest salary is 200. If there is no second highest salary, then the query should return null.
題目來源：https://leetcode.com/problems/second-highest-salary/

代碼

先找出最高的工資，就是括號裏面的那條select語句，然後再從不等於最高工資的所有記錄裏找出最高的。不等於最高工資的所有記錄裏最高的工資就是第二高的工資啦。

# Write your MySQL query statement below
select max(Salary) from Employee where Salary <> (
 select max(Salary) from Employee
);