Assignment screen audit report with grade steps included

Question

I want to create a report such that when ever a start date and end date parameters are passed to this report it will display the output of all the details on the employee's assignment screen.
for example if there has been any change in the grade or staus or payroll and grade step for this assignment (changes were done between JAN to MAR 2010)then the report must display it in the output the update that was made to the field (that is one column will be data before change and the other column would be lets say data after change (Eg. Start Date =01-JAN-2010 and End Date= 31-MAR-2010). The report query that i want is some what similar to the functionality of APPS "Date Track History" but in my report i want only to view the history between the dates passed in the parameters (i.e 01-JAN-2010 to 31-MAR-2010) .
Please help!

Answer 1

Try query of something like below. Recheck the Outer joins.
SELECT <Columns>
FROM per_all_people_f papf,
per_all_assignments_f paaf1,
per_all_assignments_f paaf2
pay_all_payrolls_f ppa1,
pay_all_payrolls_f ppa2,
per_assignment_status_types past1,
per_assignment_status_types past2
WHERE papf.person_id = paaf1.person_id
AND papf.person_id = paaf2.person_id
AND paaf1.assignment_id = paaf2.assignment_id
AND paaf1.payroll_id = ppa1.payroll_id (+)
AND paaf1.assignment_status_type_id = past1.assignment_status_type_id
AND paaf2.payroll_id = ppa2.payroll_id (+)
AND paaf2.assignment_status_type_id = past2.assignment_status_type_id
AND (NVL(paaf1.payroll_id,-1) <> NVL(paaf2.payroll_id,-1) OR paaf2.assignment_status_type_id <> paaf1.assignment_status_type_id)
AND paaf1.effective_end_date = paaf2.effective_start_date + 1
AND paaf1.effective_start_date BETWEEN papf.effective_start_date AND papf.effective_end_date
AND paaf1.effective_start_date BETWEEN ppa1.effective_start_date AND ppa1.effective_end_date
AND paaf2.effective_start_date BETWEEN ppa2.effective_start_date AND ppa2.effective_end_date
AND paaf1.effective_end_date BETWEEN :pStartDate AND :pEndDate
UNION ALL
SELECT <Columns >
FROM per_all_people_f papf,
per_all_assignments_f paaf,
per_spinal_point_placements_f pspp1,
per_spinal_point_placements_f pspp2
WHERE papf.person_id = paaf.person_id
AND pspp1.assignment_id = paaf.assignment_id
AND pspp2.assignment_id = paaf.assignment_id
AND NVL(pspp1.step_id,-1) <> NVL(pspp2.step_id,-1)
AND pspp1.effective_end_date = pspp2.effective_start_date - 1
AND pspp1.effective_start_date BETWEEN paaf.effective_start_date AND paaf.effective_end_date
AND pspp1.effective_start_date BETWEEN papf.effective_start_date AND paaf.effective_end_date
AND pspp1.effective_end_date BETWEEN :pStartDate AND :pEndDate