Re: Database design, Keys and some other things

From: mAsterdam <mAsterdam_at_vrijdag.org>
Date: Sat, 01 Oct 2005 17:47:19 +0200
Message-ID: <433eaf07$0$11065$e4fe514c@news.xs4all.nl>

Marshall Spight wrote:
> mAsterdam wrote:
>

>>Marshall Spight wrote:
>>
>>>>There is an important difference. Unless we are talking about
>>>>that specific "*some*" database, the VIN is /not/ a surrogate key in
>>>>the database at hand.
>>>
>>>So you are saying that whether something is a surrogate key
>>>or not is determined within the context of a specific database?
>>
>>Just as the key-ness of something is.
>>Is column x a key for table y?
>>The question only makes sense within the context
>>of a specific database.

>
> Okay. It strikes me, though, that this leads directly
> to a refutation of the idea that there's any essential
> difference between the industry standard external
> identifier and the database-specific surrogate key:
> it's a matter of context merely, and not anything
> intrinsic to that data, or how it is managed.

Emphasizing your /only/ in "only in the minds of the users" and /merely/ in "a matter of context /merely/", I'ld say the minds of users and context are as essential as it gets.

What would be essential in your view? Received on Sat Oct 01 2005 - 10:47:19 CDT