查看oracle系统时间

select TZ_OFFSET('PRC'),
       CURRENT_DATE,
       CURRENT_TIMESTAMP,
       LOCALTIMESTAMP,
       DBTIMEZONE,
       SESSIONTIMEZONE,
       SYSTIMESTAMP,
       SYSDATE
  from dual;

select sysdate from dual;
alter system set fixed_date = '2011-03-18 17:30';