Query : Job Change Date

select papf.employee_number,max(oldpaaf.effective_end_date +1) "Job Change Date"
from per_all_people_f papf,
per_all_assignments_f oldpaaf,
per_all_assignments_f newpaaf
where papf.person_id = oldpaaf.person_id
and papf.person_id = newpaaf.person_id
and oldpaaf.job_id != newpaaf.job_id
and oldpaaf.effective_end_date < newpaaf.effective_start_date
and trunc(sysdate) between papf.effective_start_date and papf.effective_end_date
and trunc(sysdate) between newpaaf.effective_start_date and newpaaf.effective_end_date
group by papf.employee_number