如何获取Oracle 11g中两个日期之间的天数？

Question

我试图在Oracle 11g中找到两个日期之间的整数天数.

我可以靠近做

select sysdate - to_date('2009-10-01', 'yyyy-mm-dd') from dual

但这会返回一个间隔,而我还没有成功将其转换为整数.

编辑:显然在10g中,这将以整数形式返回天数.

Answer 1

或者你可以做到这一点:

select trunc(sysdate) - to_date('2009-10-01', 'yyyy-mm-dd') from dual

这将返回一整天的NUMBER个:

SQL> create view v as 
  2  select trunc(sysdate) - to_date('2009-10-01', 'yyyy-mm-dd') diff 
  3  from dual;

View created.

SQL> select * from v;

      DIFF
----------
        29

SQL> desc v
 Name                   Null?    Type
 ---------------------- -------- ------------------------
 DIFF                            NUMBER(38)

Answer 2

我自己想通了.我需要

select extract(day from sysdate - to_date('2009-10-01', 'yyyy-mm-dd')) from dual

Answer 3

您可以尝试使用：

select trunc(sysdate - to_date('2009-10-01', 'yyyy-mm-dd')) as days from dual