1、默认sysdate输出到dual,只有日期
2、设置参数:NLS_DATE_FORMAT
(1)会话级别(当前会话,立即生效)
SQL> ALTER SESSION SET NLS_DATE_FORMAT = 'DD-MON-YYYY HH24:MI:SS' ;
(2)系统级别(重启数据库生效)
SQL>ALTER system SET NLS_DATE_FORMAT = 'DD-MON-YYYY HH24:MI:SS' scope=spfile ;
SQL> ALTER SESSION SET NLS_DATE_FORMAT = 'DD-MON-YYYY HH24:MI:SS' ;
SQL>ALTER system SET NLS_DATE_FORMAT = 'DD-MON-YYYY HH24:MI:SS' scope=spfile ;