sql find second highest salary employee

1Both options you find max as a subset and then exclude from main select
2sql> SELECT MAX( col ) FROM table
3 	WHERE col < ( SELECT MAX( col ) FROM table);
4sql> SELECT MAX(col) FROM table 
5WHERE col NOT IN (SELECT MAX(col) FROM table);

1/* sql 2nd highest salary employee */
2select sal, ename
3from emp
4where sal =
5    (
6        select max(sal) from emp where sal <
7            (select max(sal) from emp)
8    )
9----------------------------------------------- option 2
10select *
11from 
12(
13    select ename, sal, dense_rank() over(order by sal desc) rank
14    from emp
15)
16where rank =2;

1/*  Highest salary by Department/Location   */
2SELECT e.ename, e.sal, e.deptno, d.loc
3FROM emp e
4JOIN dept d
5ON e.deptno = d.deptno
6WHERE e.sal in
7( 	
8  	select max(sal) 
9  	from emp 
10  	group by deptno
11)