各位大哥大姐，我想在BAT中获取当前时间前三个月的日期，这个脚本该怎么写

Question

在BAT中，比如今天为20090302，那我想获取三个月前的日期，如1202，1203...0301，应该可以获取日期的字符串之类的，呵呵。

Answer 1

--获取两时间月份差
select (EXTRACT(year FROM to_date('2009-05-01','yyyy-mm-dd')) - EXTRACT(year FROM to_date('2008-04-30','yyyy-mm-dd'))) * 12 + 
       EXTRACT(month FROM to_date('2008-05-01','yyyy-mm-dd')) - EXTRACT(month FROM to_date('2008-04-30','yyyy-mm-dd')) months
from dual;
/*
MONTHS
----------
        13
1 row selected
*/select * from tb
where (EXTRACT(year FROM to_date(getdate,'yyyy-mm-dd')) - EXTRACT(year FROM to_date(dt,'yyyy-mm-dd'))) * 12 + 
       EXTRACT(month FROM to_date(getdate,'yyyy-mm-dd')) - EXTRACT(month FROM to_date(dt,'yyyy-mm-dd')) months = 3

Answer 2

参考:
http://jorkin.reallydo.com/article.asp?id=529

Answer 3

SQL> select add_months(sysdate, -3) from dual;ADD_MONTHS(SYSDATE,
-------------------
2008-12-02 12:07:40

Answer 4

各位，我不是说要获取某一个日期，也不是要比较两个时间的日期差，我是要获取当前日期的三个月前的所有日期，比如以下为获取当天日期
@echo   off   
set mmdd=%date:~5,2%%date:~8,2%
set mm=%date:~5,2%
我这里每天都有历史表，比如t_0101test,t_0102test,我就是把这些表给列出来，就是要把0101,0102之类的变量日期给获取出来，呵呵。

Answer 5

SQL>SQL> ed               
Wrote file afiedt.buf   1  declare
  2      l_date date;
  3  begin           
  4      l_date := trunc(add_months(sysdate,-&month));
  5      while (l_date <= trunc(sysdate) )            
  6      loop                                         
  7        dbms_output.put_line(l_date);              
  8        l_date := l_date + 1;                      
  9      end loop;                                    
 10* end;                                             
SQL> /                                                
Enter value for month: 1                              
old   4:     l_date := trunc(add_months(sysdate,-&month));
new   4:     l_date := trunc(add_months(sysdate,-1));     
2009-02-02 00:00:00                                       
2009-02-03 00:00:00                                       
2009-02-04 00:00:00
2009-02-05 00:00:00
2009-02-06 00:00:00
2009-02-07 00:00:00
2009-02-08 00:00:00
2009-02-09 00:00:00
2009-02-10 00:00:00
2009-02-11 00:00:00
2009-02-12 00:00:00
2009-02-13 00:00:00
2009-02-14 00:00:00
2009-02-15 00:00:00
2009-02-16 00:00:00
2009-02-17 00:00:00
2009-02-18 00:00:00
2009-02-19 00:00:00
2009-02-20 00:00:00
2009-02-21 00:00:00
2009-02-22 00:00:00
2009-02-23 00:00:00
2009-02-24 00:00:00
2009-02-25 00:00:00
2009-02-26 00:00:00
2009-02-27 00:00:00
2009-02-28 00:00:00
2009-03-01 00:00:00
2009-03-02 00:00:00PL/SQL procedure successfully completed.
SQL>