学习了group by ,
create function name(N int) returns INT
begin
returns ()
end
表: Employee
+-------------+------+
| Column Name | Type |
+-------------+------+
| id | int |
| salary | int |
+-------------+------+
Id是该表的主键列。
该表的每一行都包含有关员工工资的信息。
编写一个SQL查询来报告 Employee 表中第 n 高的工资。如果没有第 n 个最高工资，查询应该报告为 null 。
查询结果格式如下所示。
示例 1:
输入:
Employee table:
+----+--------+
| id | salary |
+----+--------+
| 1 | 100 |
| 2 | 200 |
| 3 | 300 |
+----+--------+
n = 2
输出:
+------------------------+
| getNthHighestSalary(2) |
+------------------------+
| 200 |
+------------------------+
示例 2:
输入:
Employee 表:
+----+--------+
| id | salary |
+----+--------+
| 1 | 100 |
+----+--------+
n = 2
输出:
+------------------------+
| getNthHighestSalary(2) |
+------------------------+
| null |
+------------------------+
来源：力扣（LeetCode）
链接：https://leetcode.cn/problems/nth-highest-salary
著作权归领扣网络所有。商业转载请联系官方授权，非商业转载请注明出处。
CREATE FUNCTION getNthHighestSalary(N INT) RETURNS INT
BEGIN
set N=N-1
RETURN (
# Write your MySQL query statement below.
select salary
from Employee
order by salary
limit 1 offset N
);
END
标签：salary,薪水,Employee,+----+--------+,+------------------------+,getNthHighestSalar From： https://www.cnblogs.com/caoke/p/16779918.html