CREATE OR REPLACE VIEW sdu.max_seq_tot_ports (
   id,
   customer,
   switch_name,
   sequence,
   ports )
AS
SELECT a.ID, b.CUSTOMER, b.SWITCH_NAME, b.SEQUENCE, SUM(b.COUNT_X)
FROM  SDU_SWITCHES a , SDP_QUERY_RESULTS b
WHERE a.SWITCH_NAME = b.SWITCH_NAME
AND a.CUSTOMER = b.CUSTOMER
AND (b.SWITCH_NAME, b.SEQUENCE) IN
(
  SELECT SWITCH_NAME, MAX(SEQUENCE)
  FROM  SDP_QUERY_RESULTS
  GROUP BY SWITCH_NAME
)
GROUP BY a.ID, b.CUSTOMER, b.SWITCH_NAME, b.SEQUENCE
/