How to find order header information

SELECT ooh.order_number, ooh.header_id hdr_id,

       DECODE (ooh.order_category_code,

               'MIXED', 'Mixed',

               'ORDER', 'Regular',

               'RETURN', 'Return',

               ooh.order_category_code

              ) CATEGORY,

       ott.NAME ord_typ, ooh.ordered_date, ooh.transactional_curr_code curr,

       os2.NAME sdt, ooh.source_document_id sdi, os1.NAME os,

       ooh.orig_sys_document_ref osdr, ooh.sold_to_org_id sold_to,

       ooh.invoice_to_org_id invoice_to, ooh.cust_po_number cust_po,

       ooh.payment_type_code pay_type, ooh.flow_status_code hdr_flow_status,

       ooh.open_flag, ooh.booked_flag, ooh.cancelled_flag,

       NVL (ooh.upgraded_flag, 'N') upgraded_flag

  FROM oe_order_headers_all ooh,

       oe_transaction_types_tl ott,

       oe_order_sources os1,

       oe_order_sources os2

 WHERE ooh.order_number = &order_number

   AND ooh.order_type_id = ott.transaction_type_id

   AND ooh.order_source_id = os1.order_source_id(+)

   AND ooh.source_document_type_id = os2.order_source_id(+)

   AND ott.LANGUAGE = (SELECT fl.language_code

                         FROM fnd_languages fl

                        WHERE fl.installed_flag = 'B');