Query to Find Requisition Number from Purchase Order Number

Query to find the purchase order number from requisition number:

SELECT DISTINCT pha.segment1
FROM po_headers_all pha,po_distributions_all pda,po_req_distributions_all rda,
po_requisition_headers_all rha,po_requisition_lines_all rla
WHERE 1=1
AND pha.po_header_id=pda.po_header_id
AND pda.req_distribution_id=rda.distribution_id
AND rda.requisition_line_id=rla.requisition_line_id
AND rla.requisition_header_id=rha.requisition_header_id
AND rha.segment1=:P_REQ_NUM

Query to find the requisition number from purchase order number:

SELECT DISTINCT rha.segment1
FROM po_requisition_headers_all rha,po_requisition_lines_all rla,
po_req_distributions_all rda,po_distributions_all pda,po_headers_all pha
WHERE 1=1
AND rha.requisition_header_id=rla.requisition_header_id
AND rla.requisition_line_id=rda.requisition_line_id
AND rda.distribution_id=pda.req_distribution_id
AND pda.po_header_id=pha.po_header_id
AND pha.segment1=:P_PO_NUMBER