department-highest-salary

Description

The Employee table holds all employees. Every employee has an Id, a salary, and there is also a column for the department Id.

Id	Name	Salary	DepartmentId
1	Joe	70000	1
2	Henry	80000	2
3	Sam	60000	2
4	Max	90000	1

The Department table holds all departments of the company.

Id	Name
1	IT
2	Sales

Write a SQL query to find employees who have the highest salary in each of the departments. For the above tables, Max has the highest salary in the IT department and Henry has the highest salary in the Sales department.

Department	Employee	Salary
IT	Max	90000
Sales	Henry	80000

Solution

select `Department`.`Name` as `Department`, `e1`.`Name` as `Employee`,
`e1`.`Salary` from `Employee` `e1` join `Department` on `Department`.`Id` = `e1`.`DepartmentId`
where `e1`.`Salary` >= (select max(`Salary`) from `Employee` where `Employee`.`DepartmentId` = `e1`.`DepartmentId`);

Note

If you have a better solution, you can star and fork Leetcode-database-problem then create a pull request.