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_at_news.xs4all.nl>
>
> 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.
Date: Sat, 01 Oct 2005 17:47:19 +0200
Message-ID: <433eaf07$0$11065$e4fe514c_at_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 - 17:47:19 CEST