Re: One-To-One Relationships

From: paul c <toledobythesea_at_ooyah.ac>
Date: Fri, 30 Nov 2007 23:01:21 GMT
Message-ID: <5D04j.8711$UQ1.1747_at_pd7urf1no>

Tegiri Nenashi wrote:
[Quoted] [Quoted] > 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? Received on Sat Dec 01 2007 - 00:01:21 CET