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Months_between(’01-sep-95’, ’11-jan-94’)
½á¹ûÊÇ£º19.6774194
 
Add_months ÔÚÖ¸¶¨µÄÔ·ÝÉÏÃæÔö¼ÓÏàÓ¦µÃÔ·Ý
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Add_months(’11-jan-94’, 6)
½á¹ûÊÇ£º11-jul-94
 
Next_day ¼ÆËã¹æ¶¨Èͮ򵀼óÒ»¸öÌØ¶¨ÈÕÆÚ
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Next_day(’01-sep-95’, ‘Friday’ )
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08-sep-95
 
Last_day Ö¸Õâ¸öÔÂ×îºóÒ»Ìì
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Last_day(’01-feb-95’) 
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select MONTHS_BETWEEN('24-2ÔÂ-2010','24-2ÔÂ-2010') from dual¡£ÕâÑùдºÜ²»·½±ã£¬ÎªÁ˱ÜÃâ³öÏÖÕâÑùµÄÎÊÌ⣬ÔÚ×Ô¼ºÊéдÈÕÆÚʱ£¬×îºÃÓÃ×Ô¼ºÏ²»¶µÄ·½Ê½Êéд£¬²¢ÓÃto_dateº¯ÊýÖ¸¶¨¸ñʽÈ磺
select MONTHS_BETWEEN(to_date('20100224','yyyymmdd'),to_date('20100524','yyyymmdd')) from dual 
ÕâÀïÉæ¼°µ½Ò»¸öto_dateº¯Êý£¬Ëü½«ÊäÈëµÄ×Ö·û´®ÐòÁУ¬×ª»»ÎªÖ¸¶¨¸ñʽµÄÈÕÆÚº¯Êý£¬ÓÉ´Ë¿ÉµÃÆäËü¸üÎªÈ«ÃæµÄʵÀýΪ£¨ÒÔϲ¿·ÖÕª×Ôhttp://blog.csdn.net/sxpyrgz£©£º
1.ADD_MONTHS 
Ôö¼Ó»ò¼õÈ¥ÔÂ·Ý 
SQL> select to_char(add_months(to_date('199912','yyyymm'),2),'yyyymm') from dual; 
TO_CHA 
------ 
200002 
SQL> select to_char(add_months(to_date('199912','yyyymm'),-2),'yyyymm') from dual; 
TO_CHA 
------ 
199910 
2.LAST_DAY 
·µ»ØÈÕÆÚµÄ×îºóÒ»Ìì 
SQL> select to_char(sysdate,'yyyy.mm.dd'),to_char((sysdate)+1,'yyyy.mm.dd') from dual; 
TO_CHAR(SY TO_CHAR((S 
---------- ---------- 
2004.05.09 2004.05.10 
SQL> select last_day(sysdate) from dual; 
LAST_DAY(S 
---------- 
31-5ÔÂ -04 
3.MONTHS_BETWEEN(date2,date1) 
¸ø³ödate2-date1µÄÔÂ·Ý 
SQL> select months_between('19-12ÔÂ-1999','19-3ÔÂ-1999') mon_between from dual; 
MON_BETWEEN 
----------- 
9 
SQL>selectmonths_between(to_date('2000.05.20','yyyy.mm.dd'),to_date('2005.05.20','yyyy.mm.dd')) mon_betw from dual; 
MON_BETW 
--------- 
-60 
×¢£ºSELECT months_between(SYSDATE, sysdate) same, 
months_between(SYSDATE, add_months(sysdate, -1)) big, 
months_between(SYSDATE, add_months(sysdate
    
     
	
	
    
    
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