1、日期转换

select to_date('2014-11-27','yyyy-MM-dd')  from dual;

select to_date('20141127','yyyyMMdd')     from dual;

select to_date('20141127','yyyy-MM-dd') from dual;

select to_date('2004-11-27 00:00:00','yyyy-MM-dd hh24:mi:ss') from dual;

select to_date(TRUNC('20141127'),'yyyy-MM-dd') from  dual;

2、无效月份

select to_date('2014-11-27','yyyyMMdd')  from dual;
不能这样转换