SELECT *
FROM   ( SELECT DISTINCT 'FYI'          action
         ,      wfi.display_name        item_type
         ,      wfma.message_type       item_type_internal
         ,      wfmt.display_name       message_name
         ,      wfma.message_name       message_internal
         FROM   wf_message_attributes   wfma
         ,      wf_item_types_tl        wfi
         ,      wf_messages_tl          wfmt
         WHERE  wfma.SUBTYPE     != 'RESPOND'
         AND    wfma.message_type = wfi.name
         AND    wfma.message_type = wfmt.type
         AND    wfma.message_name = wfmt.name
         AND    (wfma.message_type, wfma.message_name) NOT IN ( SELECT DISTINCT wfma2.message_type
                                                                ,      wfma2.message_name
                                                                FROM   wf_message_attributes   wfma2
                                                                WHERE  wfma2.SUBTYPE      = 'RESPOND'
                                                              )
         UNION
         SELECT DISTINCT 'Response Required'
         ,      wfi.display_name        item_type
         ,      wfma.message_type       item_type_internal
         ,      wfmt.display_name       message_name
         ,      wfma.message_name       message_internal
         FROM   wf_message_attributes   wfma
         ,      wf_item_types_tl        wfi
         ,      wf_messages_tl          wfmt
         WHERE  wfma.SUBTYPE     = 'RESPOND'
         AND    wfma.message_type = wfi.name
         AND    wfma.message_type = wfmt.type
         AND    wfma.message_name = wfmt.name
       ) messages
ORDER BY item_type_internal, message_internal