text: /*
  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.
  */
  -- Solution 1:
  SELECT d.Name AS Department,
         temp.Name AS Employee,
         temp.Salary
  FROM
      ( SELECT Name,
               Salary,
               DepartmentId,
               DENSE_RANK() OVER(PARTITION BY DepartmentId
                                  ORDER BY Salary DESC) AS rank
       FROM Employee
       WHERE rank <= 3 ) AS temp
  JOIN Department AS d ON temp.DepartmentId = d.Id
  GROUP BY d.Name
  ORDER BY temp.Salary;
  
  -- Solution 2
  Select dep.Name as Department,
         emp.Name as Employee,
         emp.Salary
  from Department dep,
       Employee emp
  where emp.DepartmentId=dep.Id
      and
          (Select count(distinct Salary)
           From Employee
           where DepartmentId=dep.Id
               and Salary>emp.Salary)<3