PO not INVOICED Query in R12

  SELECT   *

    FROM   po_headers_all

   WHERE   po_header_id NOT IN (SELECT   po_header_id

                                  FROM   ap_invoice_lines_all

                                 WHERE   po_header_id IS NOT NULL)

                                 and AUTHORIZATION_STATUS = 'APPROVED'

                                 and org_id =839

ORDER BY   po_header_id DESC