Description:

Write a SQL query to get the nth highest salary from the Employee table.

+----+--------+
| Id | Salary |
+----+--------+
| 1 | 100 |
| 2 | 200 |
| 3 | 300 |
+----+--------+

For example, given the above Employee table, the nth highest salary where n = 2 is 200. If there is no nth highest salary, then the query should return null.

+------------------------+
| getNthHighestSalary(2) |
+------------------------+
| 200 |
+------------------------+

Solutions:

inspired by "Discuss"

CREATE FUNCTION getNthHighestSalary(N INT) RETURNS INT
BEGIN
  SET N = N-1;
  RETURN (
      # Write your MySQL query statement below.
      SELECT (
          SELECT DISTINCT Salary
          FROM Employee
          ORDER BY Salary DESC
          LIMIT 1 OFFSET N
      )
  );
END

CREATE FUNCTION getNthHighestSalary(@N INT) RETURNS INT AS
BEGIN
    RETURN (
        /* Write your T-SQL query statement below. */
        select (
            select distinct Salary
            from
            (
                select *,
                    dense_rank() over(order by Salary desc) as rank
                from Employee
            ) as t
            where rank = @N
        ) 
    );
END