INTERVAL函数

select sysdate - INTERVAL '10' YEAR as "10年前",
sysdate - INTERVAL '10' MONTH as "10个月前",
sysdate - interval '10' day as "10天前",
sysdate - interval '10' hour as "10小时前",
sysdate - interval '10' minute as "10分钟前",
sysdate - interval '10' second as "10秒钟前",
sysdate - 10 as "10天前",
sysdate - 10 / 24 as "10小时前",
sysdate - 10 / (24 * 60) as "10分钟前",
sysdate - 10 / (24 * 3600) as "10秒钟前"
from dual;