LeetCode | database | Department Top Three Salaries

题目描述：

已知某公司员工的employee表和department表，写一个sql查询语言找出每个部门工资排前三的员工信息。

employee:



department:



输出结果：



题目解答

where条件语句的意思是：在该部门中比这三名员工中任一位工资高的人不超过3人。

SELECT d.Name AS 'Department', e1.Name AS 'Employee', e1.Salary
FROM
Employee e1
JOIN
Department d ON e1.DepartmentId = d.Id
WHERE
(SELECT
COUNT(DISTINCT e2.Salary)
FROM
Employee e2
WHERE
e2.Salary > e1.Salary
AND e1.DepartmentId = e2.DepartmentId
)<3