SubQuery in SQL

Query to Find Second Highest Salary Of Employee?

  • Interview Question: What is the Query to Find Second Highest Salary of Employee?

    Query to find Second highest salary of employee is one of the most commonly asked question in SQL interviews:

Second highest salary of employee

Answer:

     select distinct salary from Empoyee e1 where 2 = (select count(distinct salary) from Employee e2 where  e1.salary <= e2.salary);

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  •     Explaination of Query:

  

1.Distinct keyword:–>The Distinct keyword is very useful keyword which will eliminate duplicates and fetches the Result.

2.Aliases–> Alias is nothing but the obfuscation technique to protect the real names of database fields

3.Count()–>Count() function is used to count the records in the table.

Step 1: So to understand the above query we will start with simple select statement.

                Select * from Employee;

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Output:

Employee_num Employee_name Department Salary
1 Amit OBIEE 680000
2 Rohan OBIEE 550000
3 Rohit OBIEE 430000


Here our intention is to fetch the record where salary is second highest.

Step 2 :We will fetch the distinct Salary of employee and give the alias to it.

Select distinct Salary from Employee e1;

Output:

Salary
680000
550000
430000

Step 3 :We need to calculate Second highest salary.So we need to get the count of all distinct salaries.

Select count(distinct Salary) from Employee e2;

Output: 

 3

Step 4 :We actually need to calculate second highest salary.So we will modify the Step 2 query and Step3 Query:

Select distinct Salary from Employee e1 where 2=

Select count(distinct Salary) from Employee e2 where e1.salary<=e2.salary;

Output:

550000

The above query will give us the second highest salary of employee.Hope you will understand the logic behind fetching the second highest salary.There are other ways to find second highest salary of employee using rank and dense_rank function.

Other ways to find second highest salary:

Query 1:

SELECT max(e1.sal), e1.deptno FROM s_emp e1 WHERE sal < (SELECT max(sal) FROM s_emp e2 WHERE e2.deptno = e1.deptno) GROUP BY e1.deptno;

Query 2:

SELECT * FROM (SELECT S.*,DENSE_RANK() OVER (PARTITION BY DNO ORDER BY SALARY DESC) DR FROM SOURCE ) S WHERE S.DR=2;

Query 3:

Select Name From Employees Where Salary =

(Select Distinct Top(1) Salary from Employees where Salary Not In

(Select Dustinct Top(1) Salary from Employees Order By Salary Descending) Order by Salary Descending);

There are some other ways of calculating the second highest salary in different DBMS i.e. Oracle,Mysql,Postgresql:

Type 1 : Using correlated subquery:

SELECT name, salary FROM Employee e1 WHERE N-1 = (SELECT COUNT(DISTINCT salary) FROM Employee e2 WHERE e2.salary > e1.salary)SELECT name, salary FROM Employee e1 WHERE 2-1 = (SELECT COUNT(DISTINCT salary) FROM #Employee e2 WHERE e2.salary > e1.salary);

Using this method of finding out the second highest salary is slow because of the execution of inner query again and again.

Type 2: Microsoft SQL Server (Using Top Function)

SELECT TOP 1 salary FROM ( SELECT DISTINCT TOP N salary FROM Employee ORDER BY salary DESC ) AS temp ORDER BY salary;

Type3 : Mysql (using limit Clause)

SELECT salary FROM Employee ORDER BY salary DESC LIMIT 1,1;

Type 4: Oracle Function (using rownum function)

SELECT Salary FROM ( SELECT e.Salary, ROW_NUMBER() OVER (ORDER BY salary DESC) rn FROM Employee e ) WHERE rn = 2;

Type 5 : One of the website reader has suggested this solution Solution of Gautam Roy :

select * from OrderDetails a where a.Quantity < (select max(b.Quantity) from OrderDetails b) order by a.Quantity DESC limit 1;

Type 6 : Another Reader suggested solution of Bharath chary Vadla

name       sal
———-  ———————
x             120.00
y             140.00
z             200.00
p            400.00

select max(sal) as maxsalary from salary where sal < ( select max(sal) as maxsalary from salary );

Output :

maxsalary

———————

200.00

You can try this also for getting results easy

Type 7 : Suggested by one of the Reader Selva Saleen :

select salary from (select rownum row_num,salary from (select * from EMPLOYEE E order by E.salary desc))where row_num=2;

Type 8 : Find Nth Highest Salary using Limit Keyword Suggested by Reader named Dinesh Singh :

Select name, salary from employee order by salary desc limit(1,n-1);

Type 9 : New Solution for finding the second highest salary  suggested by reader named Victor :

select distinct e2.salary
from (select A.Employee_num , A.salary , count(distinct B.salary) as salary_distinct_rank
from Employee A
left join
Employ B
where B.salary <= A.salary
group by A.Employee_num, A.salary ) e2
where e2.salary_distinct_rank = 2 ;

Type 10 : New Solution for finding the second highest salary  suggested by reader named Nikhita:

Select TOP 1 Salary from Employee where Salary<(Select max(Salary) from Employee);

These are above methods to calculate 2nd highest salary of Employee.If you like this article then don’t forget to share it.

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31 Replies to “Query to Find Second Highest Salary Of Employee?”

  1. If I may first compliment the site, it is helping me tremendously with my studies.

    My Question is regarding a very small part of this explanation for your consideration the original solution : “select distinct salary from Empoyee e1 where 2 = (select count(distinct salary) from Employee e2 where e1.salary <= e2.salary);"

    what is the purpose/function of the "2" in the "where 2"?

    Sorry for the basic question I have not come across a source that has covered this particular use yet.

    Thank you for your time to answer this basic notion in advance

    1. You need to fragament the query in to different sections.

      Step 1 : select distinct salary from Empoyee e1 where 2 =

      The answer of this query is distinct salary of Employee

      Step 2 : Query 2
      select count(distinct salary) from Employee e2 where e1.salary <= e2.salary) Here we are taking count of distinct salary Step 3 : We want second highest salary...so we are taking 2 as a constant number..if you want 3rd higest salary you may take 3. Hope you got answer..

    2. Hi Stevan,

      select distinct salary from Empoyee e1 where 2 = (select count(distinct salary) from Employee e2 where e1.salary = a given salary. Here for each row of the outer query the given salary to the inner query changes. When outer query selects some row which holds the 2nd highest salary, the resulting inner query answer is 2, because there can only be 2 salaries >= 2nd highest salary.
      That is why the where clause is formed as “2 = “, so that when inner query results in 2, that is our answer.
      That “2 =” in itself doesn’t do much. It is the inner query which actually calculates the answer.

      I hope that clarifies your doubt.

  2. Please give suggestion for this query using rownum :

    select salary from (select rownum row_num,salary from (select * from EMPLOYEE E order by E.salary desc))where row_num=2;

  3. Hi Amit,

    I think type 4 query needs to be validate, it should be
    select sal from
    (select (e.sal),row_number() over (order by sal desc) rn from emp e group by e.sal)
    where rn=3

    1. Hi Akanksha,

      The query which you have given is calculating the third highest salary of employee.

      The query given in article is abs correct. I have checked it.

  4. select distinct salary from Empoyee e1 where 2 = (select count(distinct salary) from Employee e2 where e2.salary <= e1.salary);

    Why it has displaying 2nd least salary

  5. Hi ,what about below query ..
    Select salary from employee where salary in (select distinct salary from employee order by salary desc ) and rownum =2 ;

  6. Sorry but I am still confused about the 2 in where clause? Is it a count number for comparing the second highest salary in the inline query?Thanks in advance!

  7. I would have been more verbose

    select distinct e2.salary
    from (select A.Employee_num , A.salary , count(distinct B.salary) as salary_distinct_rank
    from Employee A
    left join
    Employ B
    where B.salary <= A.salary
    group by A.Employee_num, A.salary ) e2
    where e2.salary_distinct_rank = 2 ;

  8. Can we use this to find the second highest salary
    Select TOP 1 Salary from Employee where Salary<(Select max(Salary) from Employee)

  9. This is another way to find the solution

    Select top 1 * from Employees
    where salary NOT IN (Select Max(salary) from Employees)
    order by salary desc

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