Re: One-To-One Relationships

From: Bob Badour <bbadour_at_pei.sympatico.ca>
Date: Fri, 30 Nov 2007 19:12:34 -0400
Message-ID: <475098e5$0$5279$9a566e8b_at_news.aliant.net>

paul c wrote:

> Tegiri Nenashi wrote:
> 

>> On Nov 30, 1:44 pm, Jan Hidders <hidd..._at_gmail.com> wrote:
>>
>>> On 30 nov, 19:45, "David Cressey" <cresse..._at_verizon.net> wrote:
>>>
>>>> Here's the way I would try to unify the two concepts. Relationships
>>>> can be
>>>> binary, ternary, and so on, depending on the number of entities
>>>> involved in
>>>> a single instance of the relationship. How about considering an
>>>> entity a
>>>> "unary relationship"?
>>>
>>> Minor nitpick: that unary relation is the entity type (or class or
>>> whatever you want to call it), not the entity itself, which is of
>>> course the thing for which the unary relationship holds. Otherwise you
>>> are of course completely correct.
>>
>> So the matter reduces to relation attribute counting? Then, what
>> additional insight the "new" concepts of "entities" and "relationship"
>> add to the "relation" and "domain"?
>
> How do relations with no attributes unify?

Who said relations unify? Received on Sat Dec 01 2007 - 00:12:34 CET