Most recent edit on 2008-02-08 19:31:58 by Admin
Additions:
%%/ Object: UserDefinedFunction [dbo].[checksumVerhoeff] Script Date: 02/08/2008 15:54:28 /
Deletions:
%%(sql)/ Object: UserDefinedFunction [dbo].[checksumVerhoeff] Script Date: 02/08/2008 15:54:28 /
Edited on 2008-02-08 19:27:20 by Admin
Additions:
See WikiPedia:Verhoeff_algorithm∞
The Verhoeff algorithm, a checksum formula for error detection first published in 1969, was developed by Dutch mathematician Jacobus Verhoeff (born 1927). Like the more widely known Luhn algorithm, it works with strings of decimal digits of any length. It does a better job than the Luhn algorithm, though, in that it will detect all "transposition" errors (switching of two adjacent digits), as well as catching many other types of errors that pass the Luhn formula undetected.
Deletions:
See WikiPedia:Verhoeff∞
Edited on 2008-02-08 19:25:37 by Admin
Additions:
See WikiPedia:Verhoeff∞
Deletions:
See wikipedia:Verhoeff
Edited on 2008-02-08 19:24:29 by Admin
Additions:
Tested with MS SQLServer 2005.
Edited on 2008-02-08 19:23:46 by Admin
Additions:
/* @ACTION: 0 = Check on validity (0 return is valid, anything else is not), 1=Create checknum */
Usage for checking the validity of a number:
SELECT dbo.checksumVerhoeff([number TO be checked],0) FROM [your TABLE]
Usage for creating a check digit for a number:
SELECT dbo.checksumVerhoeff([your number],1) FROM [your TABLE]
Deletions:
/* @ACTION: 0 = Check on validity (0 retrun is valid, anything else is not), 1=Create checknum */
Oldest known version of this page was edited on 2008-02-08 19:20:27 by Admin []
Page view:
I have created a SQLServer User-Defined function for checking and creating the Verhoeff check digit.
See wikipedia:Verhoeff
/****** Object: UserDefinedFunction [dbo].[checksumVerhoeff] Script Date: 02/08/2008 15:54:28 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE FUNCTION [dbo].[checksumVerhoeff] (@NUMBER bigint, @ACTION tinyint)
/* @NUMBER IS the number TO CHECK OR TO CREATE a checkdigit FOR. */
/* @ACTION: 0 = CHECK ON validity (0 retrun IS valid, anything else IS NOT), 1=CREATE checknum */
RETURNS tinyint
WITH EXECUTE AS CALLER
AS
BEGIN
DECLARE @c tinyint
DECLARE @len int
DECLARE @m tinyint
DECLARE @n varchar(255)
DECLARE @i smallint
/* Declare the Arrays */
DECLARE @d char(100)
DECLARE @p char(80)
DECLARE @inv char(10)
SET @d='0123456789123406789523401789563401289567401239567859876043216598710432765982104387659321049876543210'
SET @p='01234567891576283094580379614289160435279453126870428657390127938064157046913258'
SET @inv='0432156789'
/* Start Processing */
SET @c = 0
SET @n = Reverse(@NUMBER)
SET @len = Len(@n)
SET @i=0
WHILE @i < @len
BEGIN
IF @ACTION = 1
BEGIN
/* Do the CalcChecksum */
SET @m = CAST(substring(@p,(((@i+1)%8)*10)+ CAST(substring(@n,@i+1,1) AS tinyint)+1,1) AS tinyint);
END
ELSE
BEGIN
/* Do the Checksum */
SET @m = CAST(substring(@p,((@i%8)*10)+ CAST(substring(@n,@i+1,1) AS tinyint)+1,1) AS tinyint);
END
SET @c = CAST(substring(@d,(@c*10+@m+1),1) AS tinyint);
SET @i=@i+1
END
IF @ACTION = 1
BEGIN
/* Do the CalcChecksum */
SET @c = CAST(substring(@inv,@c+1,1) AS tinyint)
END
RETURN(@c)
END;