Highest Salary in each department

Question

I have a table EmpDetails:

DeptID      EmpName   Salary
Engg        Sam       1000
Engg        Smith     2000
HR          Denis     1500
HR                  


        

Answer 1

I have like 2 approaches using one with Rank and the other with ROW_NUMBER

This is my sample data

Age          Name                                               Gender     Salary
----------- -------------------------------------------------- ---------- -----------
1           Mark                                               Male       5000
2           John                                               Male       4500
3           Pavan                                              Male       5000
4           Pam                                                Female     5500
5           Sara                                               Female     4000
6           Aradhya                                            Female     3500
7           Tom                                                Male       5500
8           Mary                                               Female     5000
9           Ben                                                Male       6500
10          Jodi                                               Female     7000
11          Tom                                                Male       5500
12          Ron                                                Male       5000
13          Ramani                                             Female     7000

So here is my first query to find max salary and the person with that max salary for each Gender

    with CTE as(
    select RANK() over(partition by Gender Order by Salary desc) as [Rank],* from employees)
    select * from CTE where [Rank]=1


Rank                 Age          Name                                               Gender     Salary
-------------------- ----------- -------------------------------------------------- ---------- -----------
1                    10          Jodi                                               Female     7000
1                    13          Ramani                                             Female     7000
1                    9           Ben                                                Male       6500

So in this case, we can see there is a tie between these 2 female employees "Jodi" and "Ramani". In that case, As a tie-breaker I want to make use of Age as a deciding factor and person with more age is supposed to be displayed

with CTE as(
select RANK() over(partition by Gender Order by Salary desc,age desc) as [Rank],* from employees)
select * from CTE where [Rank]=1

Rank                 Age          Name                                               Gender     Salary
-------------------- ----------- -------------------------------------------------- ---------- -----------
1                    13          Ramani                                             Female     7000
1                    9           Ben                                                Male       6500

Usually, in this case for finding the highest salary, it doesn't make much difference even if Rank, Dense_Rank, or Row_Number() are used. But they have some impact in other cases.

Answer 2

select a.*
 from EmpDetails a
 inner join 
 (
 select DeptID,max(Salary) as Salary
 from EmpDetails group by DeptID  
 )b 
on a.DeptID = b.DeptID and a.Salary = b.Salary

Answer 3

SELECT DeptID, MAX(Salary)
 FROM EmpDetails
GROUP BY DeptID

This query will work fine, but the moment if you want to fetch some others details related to the employee having the highest salary will contradict. You can use :

SELECT DepatID, a , b, c
 FROM EmpDetails
 WHERE Salary IN (
    SELECT max(Salary)
      FROM EmpDetails
     GROUP BY DeptID
 );

if you will use the previous query it will only reflects the records of the min val except the salary as you have used the max function.

Answer 4

This is the best possible solution for ORACLE:

Select * from (select customerid, city, freight,
row_number() over (partition by customerid order by freight desc) Row_Number from 
(select orders.orderId, customers.CUSTOMERID, customers.city, orders.FREIGHT from orders inner join customers on orders.customerid = customers.customerid where customers.country='Germany' order by customers.customerid, orders.freight desc) 
order by customerid, freight desc) where Row_Number<=2;

Notice here I have used partition by clause for marking row number, this is majorly because we need to partition the records grouping them according to customer id. I have used two inner queries here. The inner most query is to give a view which is sorted according to customer ID and decreasing order of cost. Now from that we need to obtain always top two records so firstly we need to name them and then we need to filter them according to rownum. Second level query is to mark rownum according to customer ID. And final query will filter the result according to rownum. For every partition.

Answer 5

This will work if the department, salary and employee name are in the same table.

select ed.emp_name, ed.salary, ed.dept from
(select max(salary) maxSal, dept from emp_dept group by dept) maxsaldept
inner join emp_dept ed
on ed.dept = maxsaldept.dept and ed.salary = maxsaldept.maxSal

Is there any better solution than this?

Answer 6

select deptid, empname, salary from
(Select deptid, empname,salary,
rank() Over(Partition by deptid  order by salary desc)as rank from 
EmpDetails) emp 
where emp.rank = 1

First ranks each employee by salary in descending order having highest rank 1 and then selects only deptid, empname, salary. You can do this for all Nth member of the group.