Find second largest value / Salary using Mysql

Using Sub query

Option Query 1

  SELECT MAX(salary) FROM emp WHERE salary NOT IN
 (SELECT MAX(salary) FROM emp)


Option Query 2

     SELECT MAX(salary) FROM emp WHERE salary <(SELECT MAX(salary) FROM emp)

Option Query 3
    SELECT MIN (salary) FROM emp WHERE salary in (SELECT TOP 2 (salary) FROM emp ORDER BY salary DESC)