1.取年份、月份、日数。
select extract(day from sysdate) "This day",
extract(month from sysdate) "This Month",
extract(year from sysdate) "This year"
from dual;
2.localtimestamp()返回会话中的日期和时间
select localtimestamp from dual;
current_date()返回当前会话时区中的当前日期
3.Months_between(f,s) 日期f和s间相差月数
SQL> select months_between(sysdate,to_date('2005-11-12','yyyy-mm-dd'))from dual;