oracle日期时间函数

select*from aa
where t>=to_date('2011-01-01','yyyy-mm-dd') and t <=to_date('20011-10-20','yyyy-mm-dd')

 

select*from aa
where t>=trunc('2011-01-01') and t <=trunc('20011-10-20')

--mi才是分钟，跟java有点不同

select to_char(sysdate，'yyyy/mm/dd hh:mi:ss'）from dual;