SQL> select to_date('01-JAN-13')+.99999 from dual;
TO_DATE('01-JAN-13')+.99999
---------------------------
2013-1-1 23:59:59
SQL> select to_date('01-JAN-13')+.999994 from dual;
TO_DATE('01-JAN-13')+.999994
----------------------------
2013-1-1 23:59:59
SQL> select to_date('01-JAN-13')+.999995 from dual;
TO_DATE('01-JAN-13')+.999995
----------------------------
2013-1-2
SQL> select to_date('01-JAN-13')+.999999 from dual;
TO_DATE('01-JAN-13')+.999999
----------------------------
2013-1-2
转载于:https://blog.51cto.com/traveler/1128377