标签：bsp sql查询 查询 tin mysql 信息 sql 意思 rand
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 | +------------+----------+--------+
select d.Name Department,e1.Name Employee,e1.Salary
from Employee e1,Department d where e1.DepartmentId=d.Id and
(select count(distinct e2.Salary) from Employee e1,Employee e2 where e1.DepartmentId=e2.DepartmentId and e2.Salary>e1.Salary)<3
order by d.Name,e1.Salary DESC
意思就是：我们要查询的这个人，在这部门中工资比他高的少于3个人（0,1,2人）。
括号里面是查询在这部门中工资比他高的人的数量。
标签：bsp sql查询 查询 tin mysql 信息 sql 意思 rand
原文地址：https://www.cnblogs.com/xiaojinniu425/p/9403572.html
