Re: Newbie question
Date: Wed, 22 Jun 2005 19:54:21 +0100
Message-ID: <42b9b3de$0$30831$ed2619ec_at_ptn-nntp-reader01.plus.net>
Jon Heggland wrote:
>>I guess it's a practical consideration so that simple typos can be >>trapped by the client, to save hitting the database server. In some >>scenarios this could be useful.
>
> It does mean you'll have to maintain consistency between the server-side
> and client-side checksum algorithms, though.
> And there is no guarantee
> you won't be able to enter a non-existing yet valid key (i.e. with
> correct check digits), is there? And doing the lookup gives the user
> feedback that s/he actually entered the right key, not just a well-
> formed one.
True again, there is no guarantee someone won't type in another valid key, but it does knock out the vast majority of mistakes. I guess the most common error is to make a mistake in a single character (writing a 1 as a 7 for example). I think that checksums are specifically designed to ensure that changing any one character will invalidate the checksum. I could be wrong here but if not, they certainly would take care of most cases.
Paul. Received on Wed Jun 22 2005 - 20:54:21 CEST