一个视图的写法，在线急等，多谢

Question

create or replace view b as
select opentime,closetime,
decode(to_char(closetime),'0000','1440',to_char(to_number(closetime)-to_number(opentime)))  inservtime from a

Answer 1

SELECT OPERTIME,
       CLOSETIME,
       (CASE
         WHEN CLOSETIME = '0000' THEN
          '1440'
         ELSE
          TO_CHAR(TO_NUMBER(CLOSETIME) - TO_NUMBER(A.OPERTIME))
       END) INSERVTIME
  FROM A

Answer 2

SELECT OPERTIME,
       CLOSETIME,
       DECODE(CLOSETIME,
              '0000',
              '1440',
              TO_CHAR(TO_NUMBER(CLOSETIME) - TO_NUMBER(A.OPERTIME))) INSERVTIME
  FROM A