185. Department Top Three Salaries

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

`+----+-------+--------+--------------+| Id | Name  | Salary | DepartmentId |+----+-------+--------+--------------+| 1  | Joe   | 85000  | 1            || 2  | Henry | 80000  | 2            || 3  | Sam   | 60000  | 2            || 4  | Max   | 90000  | 1            || 5  | Janet | 69000  | 1            || 6  | Randy | 85000  | 1            || 7  | Will  | 70000  | 1            |+----+-------+--------+--------------+`

The `Department` table holds all departments of the company.

`+----+----------+| Id | Name     |+----+----------+| 1  | IT       || 2  | Sales    |+----+----------+`

Write a SQL query to find employees who earn the top three salaries in each of the department. For the above tables, your SQL query should return the following rows (order of rows does not matter).

`+------------+----------+--------+| Department | Employee | Salary |+------------+----------+--------+| IT         | Max      | 90000  || IT         | Randy    | 85000  || IT         | Joe      | 85000  || IT         | Will     | 70000  || Sales      | Henry    | 80000  || Sales      | Sam      | 60000  |+------------+----------+--------+`

Explanation:

In IT department, Max earns the highest salary, both Randy and Joe earn the second highest salary, and Will earns the third highest salary. There are only two employees in the Sales department, Henry earns the highest salary while Sam earns the second highest salary.

Hint: `/*first create the Department and Employee and Salary columns in the result table*//*Remember to add Department.Name is not null*/`

Be aware of ≥ and ≤

Solution:

`select d.Name as Department,       e.Name as Employee,       Salaryfrom Employee e left join Department don e.DepartmentId = d.Idwhere(select count(distinct Salary) from Employee t1where t1.DepartmentId = d.Id and t1.Salary >= e.Salary) <= 3and d.Name is not nullorder by d.Id desc;`

Reference

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## Isabelle

In love with telling stories with data