Get Employee ID's of those employees who didn't receive incentives without using sub query ?

Question

Table Name : Employee
Employee_id First_name Last_name Salary Joining_date Department
1 John Abraham 1000000 01-JAN-13 12.00.00 AM Banking
2 Michael Clarke 800000 01-JAN-13 12.00.00 AM Insurance
3 Roy Thomas 700000 01-FEB-13 12.00.00 AM Banking
4 Tom Jose 600000 01-FEB-13 12.00.00 AM Insurance
5 Jerry Pinto 650000 01-FEB-13 12.00.00 AM Insurance
6 Philip Mathew 750000 01-JAN-13 12.00.00 AM Services
7 TestName1 123 650000 01-JAN-13 12.00.00 AM Services
8 TestName2 Lname% 600000 01-FEB-13 12.00.00 AM Insurance
Table Name : Incentives
Employee_ref_id Incentive_date Incentive_amount
1 01-FEB-13 5000
2 01-FEB-13 3000
3 01-FEB-13 4000
1 01-JAN-13 4500
2 01-JAN-13 3500

Answer 1

select EMPLOYEE_ID from EMPLOYEE
MINUS
select EMPLOYEE_REF_ID from INCENTIVES

Explanation : To filter out certain information we use MINUS command. What MINUS Command odes is that, it returns all the results from the first query, that are not part of the second query. In our example, first three employees received the incentives. So query will return employee id's 4 to 8.