【MySQL】【leetcode】 Second Highest Salary解题报告

题目

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.
题目来源：https://leetcode.com/problems/second-highest-salary/

代码

先找出最高的工资，就是括号里面的那条select语句，然后再从不等于最高工资的所有记录里找出最高的。不等于最高工资的所有记录里最高的工资就是第二高的工资啦。

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