MOD 10 (Credit Card Validation)

Does anyone have any strings or links I can use to help with creating a mod-10 stored proc?

I am really stuck on step 1, which is flipping the numbers (ex 1234 -> 4321)..

Any information pretaining to MOD-10 and MSSQL would be MUCH appriciated..Does this help you to flip the number?

declare @.in bigint
declare @.out bigint

set @.in = 123456789012345678
set @.out = 0

while @.in > 0
begin
print @.in %10
set @.out = @.out*10 + (@.in % 10)
Set @.in = @.in /10

end

select @.out|||It looks like it should work.. I'm going to try it in the morning!

Thanks!sql