Re: Entity and Identity

From: noyb <no.spam_at_please.net>
Date: Sun, 27 Sep 2009 11:17:40 +1000
Message-ID: <X2zvm.194877$8B7.134823_at_newsfe20.iad>



Walter Mitty wrote:
> "noyb" <no.spam_at_please.net> wrote in message
> news:MNgvm.29468$944.14847_at_newsfe09.iad...
>> The RM is a self-contained model, and as such, can circumscribe
>> the identity of a tuple, and it requires specifying a means to
>> identify every tuple.

> Let's not conflate the identity of a tuple with the identity of the entity
> that an item of data in the tuple pertains to.

I'm not. But O-O programmers treat their objects much as we do "natural world" objects; vis they don't concern themselves with theory, only with pragmatic results.

You failed to comment on the fact that a tuple which has more than one instantiation (location) is still *made to behave* as though it was the same object (by being confined within ACID rules). That supports your original assertion (identity derives from state only) against those who claimed that location is also part of state.

You also failed to comment on the pointers I gave to my project, which is a substantial and so-far effective attempt at getting us out of our Vietnam, by uniting the best of object and relational approaches under fact orientation. Please read carefully before dropping any more of the pugnacious one-liners that this group is known for.

--
Clifford Heath, Data Constellation, http://dataconstellation.com
Agile Information Management and Design
Received on Sat Sep 26 2009 - 20:17:40 CDT

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