Re: Table design question

On Thu, 01 Jun 2006, Chris Browne wrote:

> Celko is decidedly *NOT* promoting the notion that you should use a
> 100 byte long "natural key."
>
> Jamie's comments of "Orthodox versus Reform" seem reasonably
> appropriate in outlining something of the difference between the
> positions.

Just to be clear, that was all I was trying to do. I probably should
have mentioned that any attempt to use such an attribute as a PK should
be met with a baseball bat or other shillelagh-ish implement, but was
interrupted several times during that email drafting.

> I may not care for doing this; you may not either; a company that
> builds auto parts that they want to sell into the automotive industry
> may care about standardizing their part IDs quite a lot.

This is another important point. In some situations, a rigid data model
can be a godsend to coders. If you happen to sit in such an enviable
position, I would encourage you to take advantage of it. (This doesn't
mean picking bad keys, of course.)

I liberally sprinkle surrogate keys around simply because most of the
projects I work on have transient requirements, so spontaneous rejiggery
and various pokery are both commonplace, and SKs provide "enough" data
integrity that the cost/benefit curve seems to peak there. Were I doing
projects that had longer release cycles, I'd re-evaluate that position,
and likely see a marginal reduction in bugs.

None of this should be taken as bashing Celko - he's a smart man and an
excellent source of advice.

-j

--
Jamie Lawrence jal(at)jal(dot)org
When I talked to the president, he was loaded.
- Brent Scowcroft, Kissinger's assistant, 10/11/73