回答：不同的数据库，截取时间的方法不一样，拿oracle举例，select to_char(sysdate,'yyyy-mm-dd hh24:mi:ss') as nowTime from dual;   //日期转化为字符串  select to_char(sysdate,'yyyy') as nowYear   from dual;   //获取时间的年  select to_char(sysdate,'mm')    as nowMonth from dual;   //获取时间的月  select to_char(sysdate,'dd')    as nowDay    from dual;   //获取时间的日  select to_char(sysdate,'hh24') as nowHour   from dual;   //获取时间的时  select to_char(sysdate,'mi')    as nowMinute from dual;   //获取时间的分  select to_char(sysdate,'ss')    as nowSecond from dual;   //获取时间的秒sysdate表示当前日期时间