Re: Possible bridges between OO programming proponents and relational model
Date: 5 Jun 2006 03:41:34 -0700
Message-ID: <1149504094.756973.162640_at_i40g2000cwc.googlegroups.com>
Thank you for this insight.
JXStern wrote:
> On Sun, 04 Jun 2006 17:25:04 GMT, Bob Badour
> <bbadour_at_pei.sympatico.ca> wrote:
> >Apparently, in your addressing scheme, one may not access memory through
> >a single pointer. Instead, one must use three pointers.
>
> I just wandered (back) into the newsgroup yesterday for the first time
> in a while, and onto this thread in the middle of things, and have
> only read a few exchanges, but maybe this is the crux of Cimode's
> concerns about memory yada yada.
Yes. Through this thread, I am trying to involve people *not* to have
the usual RM vs the Rest of the World debate. But try to understand
how can the only valid model be better implemented given the available
implementation mecahnisms at hand OO is one of them.
I am convinced all people here are of good faith but just lack specific
information to allow them to communicate efficiently with other type of
audiences.
>
> Odd that this thread doesn't seem to use terms like "projection" or
> "composition" (maybe I did see "decomposition"). Or, y'know,
> "semantics".
semantics and terminology are necessary to bring coherence in RM
definition. Lack of commitment to precise definition bothers RM
knowledgeable audiences. For good reasons. Projections or
compositions have not been evocated yet because there was no context
yet for them to be evocated. What do you have in mind?
> The relational model really only uses one "relation", which is
> adjacency.
I do not agree with that. RM is about defining an infinity of
relations.
Perhaps this is another Cimode concept in the making.
Could you define precisely "Adjacency". I am not certain to what it means to you.
You
> can have as many dimensions of adjacency as you like. You can
> reinterpret a dimension of adjacency as something else, like time
> sequence, but as soon as you do, you run across the limits of the
> relational model. Now, it is also the great strength of the
> relational model that it is built so simply, and the question is
> whether that strength is comprimised when we go to extend it.
I do not understand this argument. Could you ellaborate?
> I continue to be nonplussed by recent Date advocacies of sets as field
> domains. OTOH, I am also nonplussed by the industry's history of
> limiting user defined types and corresponding operators along the
> model of C++. Sure, you can make a mess (see any large C++ program
> for proof!), but that is the only technical direction from the limits
> of the current "flat" (adjacency) relational model to the fancy, rich
> New World we all want to get to.
>
> J.
Received on Mon Jun 05 2006 - 12:41:34 CEST