176.second-highest-salary.md

176. Second Highest Salary

Select the second highest distinct salary from the employee table.
We utilize IFNULL to return NULL if the nth highest salary doesn't exist.

SELECT IFNULL(
(
  SELECT DISTINCT salary
  FROM Employee
  ORDER BY salary DESC
  LIMIT 1 OFFSET 1
),
  NULL
) AS SecondHighestSalary;