Load Action History of PO through back end

How to load Action History for PO through back end?
Base Table for PO Action History?
Important scenarios for PO action History?

Load Action History of PO through back end:

Important Derivation/Validation:

Derive person id:

SELECT papf.person_id
FROM per_all_people_f papf
WHERE NVL(papf.employee_numbernpw_number) = p_emp_number
AND TRUNC (SYSDATE) BETWEEN papf.effective_start_date AND papf.effective_end_date;
OR
SELECT papf.person_id
FROM per_all_people_f papf
WHERE NVL(papf.employee_numbernpw_number) = p_emp_number
AND TRUNC (SYSDATE) BETWEEN papf.effective_start_date AND papf.effective_end_date
AND current_employee_flag = 'Y';

Derive PO header id:

SELECT DISTINCT po_header_id
FROM po_headers_all
WHERE segment1= p_po_number;

Check History is already existing or not:

SELECT 'S'
INTO l_exist
FROM po.po_action_history poh
WHERE poh.object_id= p_po_header_id_
AND poh.sequence_num = p_sequence_num
AND poh.action_code= p_action_code
AND poh.employee_id= p_person_id;

 
PO.PO_ACTION_HISTORY (Base Table):

OBJECT_ID                                  => p_po_header_id
OBJECT_TYPE_CODE                  => 'PO'
OBJECT_SUB_TYPE_CODE  => 'STANDARD'
SEQUENCE_NUM                  => p_sequence_num
LAST_UPDATE_DATE                  => sysdate
LAST_UPDATED_BY                  => fnd_global.user_id
CREATION_DATE                  => sysdate
CREATED_BY                          => fnd_global.user_id
ACTION_CODE                          => p_action_code
ACTION_DATE                          => p_action_date
EMPLOYEE_ID                          => p_employee_id
APPROVAL_PATH_ID                  => p_approval_path_id
NOTE                                          => p_note
OBJECT_REVISION_NUM          => p_object_revision_num
OFFLINE_CODE                         => p_offline_code
LAST_UPDATE_LOGIN         => fnd_global.login_id
REQUEST_ID                         => fnd_global.conc_request_id
PROGRAM_APPLICATION_ID => p_program_application_id
PROGRAM_ID                         => p_program_id
PROGRAM_UPDATE_DATE => p_program_update_date
PROGRAM_DATE                 => p_program_date
APPROVAL_GROUP_ID         => p_approval_group_id