Lets there is [Employee] table having two columns EmpName , and Salary . Something like :

EmpName	Salary
Mark	30
Jacob	70
Larry	50
John	150

First Method

select distinct salary from Employee e1 where N-1 = (select count(distinct salary) from Employee e2 where e1.salary <= e2.salary);

To understand above query lets break query into subpart:

• select count(distinct salary) from Employee e2 where 30<= e2.salary;
• select count(distinct salary) from Employee e2 where 70<= e2.salary;
• select count(distinct salary) from Employee e2 where 50<= e2.salary;
• select count(distinct salary) from Employee e2 where 150<= e2.salary;

Note: to get third highest salary, put N=4 in above query and for highest salary in entire table put N=2 and so on.

Second Method

select Top 1 EmpName ,Salary from Employee Order By Salary DESC;

This is very simple query to get highest salary of employee.

Third Method

select MAX(Salary) as HighestSalary from Employee Where Salary NOT IN ( Select Top 2 Salary From Employee Order By Salary DESC);

To get top salary getter first of all we'll get top 2 salary from table and after that we'll get top 1 from that record set.