how to write SQl query for the given problem below with a self join

[tabreaz]

Hope this will help you.

SELECT distinct grade,
        count(decode(job_type, 'Type1', 1))
                over(partition by grade) t1,
        count(decode(job_type, 'Type2', 1))
                over(partition by grade) t2,
        count(decode(job_type, 'Type3', 1))
                over(partition by grade) t3
FROM emp_grade
ORDER BY 1