oracle的时间加减

SQL> alter session set nls_date_format='yyyy-mm-dd hh24:mi:ss';

Session altered.

SQL> select sysdate, sysdate+1/24, sysdate +1/1440, sysdate + 1/86400 from dual;

SYSDATE            SYSDATE+1/24        SYSDATE+1/1440      SYSDATE+1/86400
------------------- ------------------- ------------------- -------------------
2008-04-16 21:23:19 2008-04-16 22:23:19 2008-04-16 21:24:19 2008-04-16 21:23:20
24表示是1天,1/24表示是1小时,1/1440表示1分钟,1/86400表示1秒