力扣——第二高的薪水（数据库的题

Posted 2021-02-07 jaypark

编写一个 SQL 查询，获取 Employee 表中第二高的薪水（Salary） 。

+----+--------+
| Id | Salary |
+----+--------+
| 1  | 100    |
| 2  | 200    |
| 3  | 300    |
+----+--------+

例如上述 Employee 表，SQL查询应该返回 200 作为第二高的薪水。如果不存在第二高的薪水，那么查询应返回 null。

+---------------------+
| SecondHighestSalary |
+---------------------+
| 200                 |
+---------------------+

# Write your mysql query statement below
select IFNULL((select distinct(Salary) 
from Employee
order by Salary desc
limit 1,1),null) as SecondHighestSalary