Oracle中的一些时间处理

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Oracle 中的时间处理

<!-- [if !supportLists]-->1. <!-- [endif]-->当前时间： select sysdate from dual 。

<!-- [if !supportLists]-->2. <!-- [endif]-->当期时间减去一天后的时间： select sysdate from dual 。

<!-- [if !supportLists]-->3. <!-- [endif]-->当期时间减去一小时后的时间： select sysdate - 0.041666687 from dual 。

<!-- [if !supportLists]-->4. <!-- [endif]-->得到当前年份： select to_char(sysdate, ‘YYYY’) from dual;

<!-- [if !supportLists]-->5. <!-- [endif]-->得到当前月份： select to_char(sysdate, ‘MM’) from dual;

<!-- [if !supportLists]-->6. <!-- [endif]-->得到当前天： select to_char(sysdate, ‘DD’) from dual;

<!-- [if !supportLists]-->7. <!-- [endif]-->得到当前小时： select to_char(sysdate, ‘HH24’) from dual;

<!-- [if !supportLists]-->8. <!-- [endif]-->得到当前分： select to_char(sysdate, ‘MI’) from dual;

<!-- [if !supportLists]-->9. <!-- [endif]-->得到当前秒： select to_char(sysdate, ‘SS’) from dual;

<!-- [if !supportLists]-->10. <!-- [endif]-->得到当前天和一个日期相差的天数：

select sysdate – to_date(‘2009-12-10 14:12:13’, ‘YYYY-MM-DD HH24:MI:SS’) from dual;

<!-- [if !supportLists]-->11. <!-- [endif]-->