Re: Surrogate Keys: an Implementation Issue
From: Bob Badour <bbadour_at_pei.sympatico.ca>
Date: Sat, 29 Jul 2006 20:07:47 GMT
Message-ID: <nePyg.28677$pu3.392953_at_ursa-nb00s0.nbnet.nb.ca>
>> What's the point of a database if it doesn't reflect some aspect of
>> reality. Assertions are worthless without a frame of reference. A
>> database can only guarantee consistency, not correctness. Therefore,
>> the truth of a statement comes from without the database, that is,
>> from reality. With surrogates, I can extract more meaning from a
>> database by being able to determine which premises changed and how.
Date: Sat, 29 Jul 2006 20:07:47 GMT
Message-ID: <nePyg.28677$pu3.392953_at_ursa-nb00s0.nbnet.nb.ca>
> Brian Selzer wrote: >
>> What's the point of a database if it doesn't reflect some aspect of
>> reality. Assertions are worthless without a frame of reference. A
>> database can only guarantee consistency, not correctness. Therefore,
>> the truth of a statement comes from without the database, that is,
>> from reality. With surrogates, I can extract more meaning from a
>> database by being able to determine which premises changed and how.
A hidden surrogate does not allow you to do anything you cannot already do. If one needs to know the state of the database at some point of time in the past, one needs a database that does not discard log files and that can answer queries as of any point of time in the past.
Whether entity A was at some physical location now occupied by entity B is uninteresting.
I
>> can also to avoid the problems that I described earlier.
Bullshit. He keeps asserting this nonsense but he doesn't even understand the concept of a candidate key or that it first and foremost must provide logical identity.
[Selzer's infantile and malicious comments snipped] Received on Sat Jul 29 2006 - 22:07:47 CEST