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 query should return 200
as the second highest salary. If there is no second highest salary, then the query should return null
.
+---------------------+
| SecondHighestSalary |
+---------------------+
| 200 |
+---------------------+
题目链接:https://leetcode.com/problems/second-highest-salary/
coalesce:返回表达式中第一个非空表达式
# Write your MySQL query statement below
select coalesce((select distinct salary from employee order by salary desc limit 1,1)) as SecondHighestSalary
方法二:
# Write your MySQL query statement below
select (select distinct Salary from Employee order by Salary desc limit 1,1 )as SecondHighestSalary