Galen Boyer <galenboyer_at_hotpop.com> wrote in message news:<uk7iyc0bt.fsf_at_standardandpoors.com>...
> On 27 Nov 2002, ctcgag_at_hotmail.com wrote:
> > I would rather tell someone "Let's pretend you SSN is
> > 000-00-0001 until we figure this out" than to amputate the
> > wrong person's leg.
> >
> > I'm not arguing against the use SIDs, I use them all the time.
> > I just think that you if you use a SID as the pk, but then
> > still have a natural key as a unique and not null field and
> > write the application accordingly, you probably aren't solving
> > the problems you think you are solving. If you are writing the
> > application so the the natural key is not required to be unique
> > and not null, then why have that constraint in the database?
>
> This is the point. When I started coding, I "thought" ssn's were
> unique. I then find out they aren't after the app is in
> production. With the SSN as the PK, I have a much bigger issue.
> I now have this key all over the database, and it is the
> incorrect key and will need to be changed.
>
> If I had a dummy key, then I would be able to isolate the issue
> to how to handle the SSN number. If in fixing it, like your
> example talks about, I might amputate the wrong leg, well, then
> how I deal with and fix this issue would be different. I might
> not fix it right away, but instead, tell the guy (as you said,
> lets pretend your ssn number is 000-000-0001 until we figure this
> out). But, when it came time to fix it, it would be an isolated
> fix. Maybe an extra piece of code added to the app to count how
> many rows returned and then prompt for blah... In your scenario,
> this same exact fix might be your solution as well, but you would
> have the added task of redefining your PK. So, not only do you
> have to implement the same fix I would have to, you also have to
> fix your database in a drastic fashion.
This is quick fix vs redesign question. If you prefer to have a
system where you can do quick and dirty fix, you are right. Damn
that person's leg. You're not gonna be sued for it anyway. If
your initial design assume some logical PK, all your code is
written based on this assumption. Dummy key just helps you to
do quick and dirty fix. So for the outside world your software
just pretends to work. To make clean permanent fix you need to
redesign your system anyway.
Received on Fri Nov 29 2002 - 10:40:26 CST
