Query to get po,Invoice,Receipt number

SELECT distinct pha.segment1 po_number

       ,aia.invoice_num invoice_number

       ,rsh.receipt_num receipt_number

  FROM po_headers_all pha

       ,po_distributions_all pda

       ,ap_invoice_distributions_all aid

       ,ap_invoices_all aia

       ,rcv_shipment_lines rsl

       ,rcv_shipment_headers rsh

 WHERE pha.po_header_id=pda.po_header_id

   AND aid.po_distribution_id=pda.po_distribution_id

   AND aia.invoice_id=aid.invoice_id

   AND rsl.po_header_id=pha.po_header_id

   AND rsl.shipment_header_id=rsh.shipment_header_id

   AND pha.segment1=nvl(:P_PO_NUM,pha.segment1)

   AND aia.invoice_num=nvl(:P_INVOICE_NUM,aia.invoice_num)

   AND rsh.receipt_num=nvl(:P_RECEIPT_NUM,rsh.receipt_num)

  

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