# 176. 第二高的薪水
# https://leetcode-cn.com/problems/second-highest-salary/

# SQL架构
Create table If Not Exists Employee (id int, salary int);
Truncate table Employee;
insert into Employee (id, salary) values ('1', '100');
insert into Employee (id, salary) values ('2', '200');
insert into Employee (id, salary) values ('3', '300');

# Write your MySQL query statement below
select
    ifnull(
        (
            select
                distinct salary
            from
                Employee
            order by
                salary desc
            limit
                1 offset 1
        ),
        null
    ) as SecondHighestSalary;

# clean-up
drop table Employee;