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Éí·ÝÖ¤ÑéÖ¤Ëã·¨(SQL°æ)
/**//*
ÑéÖ¤Éí·ÝÖ¤Ëã·¨
By:Áõ־ΰ
2008-1-29ÓëÌì½ò
*/
CREATE FUNCTION [fn_ValidateIDC]
(
@idc varchar(18)
)RETURNS BIT
AS
BEGIN
IF LEN(@idc)<>15 AND LEN(@idc)<>18--Éí·ÝÖ¤ºÅÖ»ÓÐ15»ò18λ
RETURN(0)
IF LEN(@idc)=15  --Èç¹ûÊÇ15λÉí·ÝÖ¤ ÔòÖ»ÑéÖ¤ÈÕÆÚºÍÊÇ·ñÊý×Ö¸ñʽ
   IF ISDATE('19'+SUBSTRING(@idc,7,6))=0 OR ISNUMERIC(@idc)=0
       RETURN(0)
    ELSE
       RETURN(1)
/**//**//**//*
18λÉí·ÝÖ¤ ÑéÖ¤ÈÕÆÚ Ð£Ñéλ
*/
IF ISDATE(SUBSTRING(@idc,7,8))=0 OR ISNUMERIC(SUBSTRING(@idc,1,17))=0--ÑéÖ¤ÈÕÆÚºÍÇ°17λÊÇ·ñÊý×Ö¸ñʽ
   RETURN(0)
/**//**//**//*Ñé֤УÑéλ¿ªÊ¼*/
DECLARE @validFactors VARCHAR(17),@validCodes VARCHAR(11),@i TINYINT,@iTemp INT
SELECT @validFactors='79A584216379A5842',@validCodes='10X98765432',@i=1,@iTemp=0
WHILE @i<18
   BEGIN
      SELECT @iTemp=@iTemp+CAST(SUBSTRING(@idc,@i,1) AS INT)*(CASE SUBSTRING(@validFactors,@i,1) WHEN 'A' THEN 10 ELSE SUBSTRING(@validFactors,@i,1) END)
            ,@i=@i+1
   END
IF SUBSTRING(@validCodes,@iTemp%11+1,1)=RIGHT(@idc,1)
   RETURN 1
ELSE
   RETURN 0
RETURN NULL
END
GO
http://www.cnblogs.com/wf5360308/articles/1251009.html