最近在刷leetcode题库，刚好看到中文网站已经上线了，新增了ms sql解释器。困难难度链接在这，就顺便吐槽一下这个中文名字吧。 [ 力扣题库 ]
185. 部门工资前三高的员工
Employee 表包含所有员工信息，每个员工有其对应的 Id, salary 和 department Id 。
| Id | Name | Salary | DepartmentId |
|---|---|---|---|
| 1 | Joe | 70000 | 1 |
| 2 | Henry | 80000 | 2 |
| 3 | Sam | 60000 | 2 |
| 4 | Max | 90000 | 1 |
| 5 | Janet | 69000 | 1 |
| 6 | Randy | 85000 | 1 |
Department 表包含公司所有部门的信息。
| Id | Name |
|---|---|
| 1 | IT |
| 2 | Sales |
编写一个 SQL 查询，找出每个部门工资前三高的员工。例如，根据上述给定的表格，查询结果应返回：
| Department | Employee | Salary |
|---|---|---|
| IT | Max | 90000 |
| IT | Randy | 85000 |
| IT | Joe | 70000 |
| Sales | Henry | 80000 |
| Sales | Sam | 60000 |
解法
select department ,employee ,salary
from (
select b.name as department ,a.name as employee ,salary
,dense_rank() over(partition by departmentid order by salary desc) as rn
from employee a
left join department b
on a.departmentid=b.id where b.name is not null) a
where rn<=3
order by department,salary desc*如有问题，敬请留言。