如何计算两个日期间隔的月数？

Question

select to_number(to_char(to_date('2003-08-31','yyyy-mm-dd'),'mm'))-to_number(to_char(to_date('2003-07-01','yyyy-mm-dd'),'mm')) from dual;

Answer 1

上面这样写好像不对啊 如果相差超过一年就有问题了:)
假设date1是日期1 date2是日期2
select (to_number(to_char(date1,'yyyy'))-to_number(to_char(date2,'yyyy')))*12+
(to_number(to_char(date1,'mm'))-to_number(to_char(date2,'mm'))) from dual;

Answer 2

select MONTHS_BETWEEN(trunc(date1,'MM'),trunc(date2,'MM')) from dual;

Answer 3

select MONTHS_BETWEEN(trunc(to_date('20050101','YYYYMMDD'),'MM'),trunc(to_date('20030201','YYYYMMDD'),'MM')) from dual

Answer 4

select trunc(months_between(sysdate,to_date('20020405','yyyymmdd'))) from dual;