how to get second highest salary department wise without using analytical functions?

Question

Suppose we have 3 employees in each department.we have total 3 departments . Below is the sample source table

Emp deptno salary
A    10     1000
B    10              


        

Answer 1

On MySQL this how you can get second highest salary, given table name is salaries:

By Nested Queries: (where you can change offset 0/1/2 for first, second and third place respectively)

select
  *
from
  salaries as t1 
where 
  t1.salary = (select 
               salary
             from 
               salaries
             where 
             salaries.deptno = t1.deptno ORDER by salary desc limit 1 offset 1);

or might be by creating rank: (where you can change rank= 1/2/3 for first, second and third place respectively)

SET @prev_value = NULL;
SET @rank_count = 0;
select * from 
(SELECT
  s.*, 
  CASE 
      WHEN @prev_value = deptno THEN @rank_count := @rank_count + 1
      WHEN @prev_value := deptno THEN @rank_count := 1 
      ELSE @rank_count := 1 
  END as rank
FROM salaries s
ORDER BY deptno, salary desc) as t
having t.rank = 2;