oracle中to_char函数操作时间对象

 
SQL> select sysdate from dual;
 
SYSDATE
-----------
2011-5-17 2

SQL> select to_char(sysdate , 'yyyy-MM-dd hh:mm:ss') from dual;
 
TO_CHAR(SYSDATE,'YYYY-MM-DDHH:
------------------------------
2011-05-17 08:05:33