Increasing Alphanumeric value in user defined function

Question

I'm trying to code a user defined function under SQL Server 2005 that will increase integer part of alphanumeric value by one. For example, uf_AlphanumericIncrease ('A000299') should return 'A000300'. Here's what I've done so far;

ALTER FUNCTION uf_AlphaNumericIncrement
(
@ID varchar(10)
)
RETURNS VARCHAR(10) AS
BEGIN
    DECLARE @RES varchar(10);
    IF SUBSTRING(@ID,LEN(@ID),1)='9'
        SET @RES=SUBSTRING(@ID,1,LEN(@ID)-2)+CAST (CAST(SUBSTRING(@ID,LEN(@ID)-1,1) AS smallint)+1 AS VARCHAR(10))+'0';
    ELSE
        SET @RES=SUBSTRING(@ID,1,LEN(@ID)-1)+CAST (CAST(SUBSTRING(@ID,LEN(@ID),1) AS smallint)+1 AS VARCHAR(10));
    RETURN @RES;
END 

But as you can see it only works for last digit. I need to get it under loop so it can work for A002999 and so on. Any ideas?

Edit: Given value might have alpha prefix longer than one character, or none at all.

Answer 1

Now works with any length of prefix and number part (well upto 20 each)

DECLARE @prefix varchar(20), @numberstr varchar(20), @number int, @Val varchar(40)

SELECT @Val = 'ABCD000006'
--SELECT @Val = 'A03'

SELECT @prefix = LEFT(@Val, PATINDEX ('%[0-9]%', @Val) -1)
SELECT @numberstr = SUBSTRING(@Val, PATINDEX ('%[0-9]%', @Val), 8000)
SELECT @number = CAST(@numberstr AS int) + 1
SELECT @prefix + RIGHT(REPLACE(SPACE(LEN(@numberstr)), ' ', '0') + CAST(@number AS varchar(20)), LEN(@numberstr))

Answer 2

CREATE FUNCTION dbo.uf_ANinc
(
  @in varchar(10)
)
RETURNS varchar(10) AS
BEGIN
    DECLARE @prefix varchar(10);
    DECLARE @res varchar(10);
    DECLARE @pad varchar(10);
    DECLARE @num int;
    DECLARE @start int;

    SET @start = PATINDEX('%[0-9]%',@in);
    SET @prefix = LEFT(@in, @start - 1 );
    SET @num = CAST(  RIGHT( @in, LEN(@in) - @start ) AS int  ) + 1
    SET @pad = REPLICATE( '0', 10 - LEN(@prefix) - CEILING(LOG(@num)/LOG(10)) );
    SET @res = @prefix + @pad + CAST( @num AS varchar);

    RETURN @res
END
GO

SELECT dbo.uf_ANinc('ABC000123');

Answer 3

Assuming that the alpha part of your alphanumeric is always only the first character, this should work.

EDIT: OK, if the alpha part varies in length this gets ugly pretty quickly for a UDF. This is just a quick-and-dirty solution, so it can probably be optimized a bit, but the logic should be sound.

EDIT AGAIN: patindex() ftw - I learned something new today ;-)

ALTER FUNCTION uf_AlphaNumericIncrement
(
@ID varchar(10)
)
RETURNS VARCHAR(10) AS
BEGIN
    DECLARE @RES varchar(10);
    DECLARE @num int;
    DECLARE @prefix varchar(10);
    set @prefix = left(@id, patindex('%[0-9]%', @id) -1)
    set @num = cast(right(@id, len(@id) - len(@prefix)) as int) + 1
    set @res = @prefix + replicate('0', len(@id) - len(@prefix) - len(@num)) + cast(@num as varchar(10))

    RETURN @RES;
END