On Mon, Apr 28, 2008 at 6:49 AM, Rob Wultsch <wultsch@gmail.com> wrote:
> I am going to assume that you are asking this question because
> performance has not improved from this change. Is this correct?
>
> I don't think that your surogate key (id) is useful, but that is
> probably minor. I think that your hostings company suggestion is
> probably a good idea, but will also probably not impact performance. A
> prymary key is basically only a unique not null key, and it sounds
> like your isbn field should have those properties.
>
> >key_len=302
> This is pretty horrible. If I needed better performance I would try to
> turn the isbn field into a bigint (the dashes are the only non-numeric
> characters and have no significance, right?). That would start with
> something like:
> ALTER TABLE `books` ADD `new_isbn` BIGINT NOT NULL ;
> UPDATE `books` SET `new_isbn` = replace(`isbn`,'-','');
> ...
> though that may require significant changes in your app (converting
> the string into an int) but a stored procedure might make this
> somewhat less painful.
>
> What are your goals here?

For the record: if performance is good enough I wouldn't change anything...

--
Rob Wultsch
wultsch@gmail.com
wultsch (aim)