Re: Surrogate primary key plus unique constraint vs. natural primary key: data integrity?

On Tue, 12 Mar 2013 11:24:19 -0700 (PDT) Cimode <cimode_at_hotmail.com> wrote:

> > It is a consequence of defining the enterprise of interest. A
> > value assigned outside the enterprise of interest that is a key
> > within it is "natural".
>
> An *enterprise of interest* does not say anything about the fact that
> a surrogate key may at some future point in time be considered a
> natural key. But the point is that subjectivity can not be taken
> from the equation in any scheme involving establishing a unique
> identifier.

I suppose you're on solid ground there, in a way. The determination of what is an entity, of what will be modelled in the database, is surely subjective. We might even say "establishing a unique identifier" is, at best, heuristic. It's unique until it's not. I remember when currency mapped 1:1 to country.

Roy's point is that the surrogate/natural nomenclature derives from (subjective) perspective. Do you disagree with that, or just think the matter too trifling to discuss?

--jkl Received on Wed Mar 13 2013 - 00:42:54 CET