sql query to get second highest salary using rownum code example

Example 1: how to get second highest salary in each department in sql

SELECT E.Employers_name, E.dep_number, E.salary
FROM Employers E
WHERE 1 = (SELECT COUNT(DISTINCT salary) 
        FROM Employers B 
        WHERE B.salary > E.salary AND E.dep_number = B.dep_number)
group by E.dep_number

Example 2: sql find second highest salary employee

/* sql 2nd highest salary employee */
select sal, ename
from emp
where sal =
    (
        select max(sal) from emp where sal <
            (select max(sal) from emp)
    )
----------------------------------------------- option 2
select *
from 
(
    select ename, sal, dense_rank() over(order by sal desc) rank
    from emp
)
where rank =2;