Re: MV counterexample

From: Dawn M. Wolthuis <dwolt_at_tincat-group.com>
Date: Thu, 6 May 2004 12:52:17 -0500
Message-ID: <c7du0o$ppc$1_at_news.netins.net>


"Laconic2" <laconic2_at_comcast.net> wrote in message news:C-qdnf_mH5pR2wfdRVn-sA_at_comcast.com...
> This is off topic, but anyway:
>
> You mentioned "di-graphs". In the original Codd article,
> he compares the data model he is proposing to the "graph and network
models"
> . I'm assuming that di-graph and graph boil down to the same thing. Is
> that so? Or is there something more I need to learn about di-graphs?

Yes, a di-graph is a directed graph so there is direction to the links (arrows on the edges). Web page content can be modeled as a di-graph, for example, with a link from one page to another (just a foreign key to the URL or key to another page).

I'm sure there are "web people" who have done more with this, but what I'm working with is a very simple di-graph with "functions" on the nodes (note that functions are a type of relation) and functions that map from one node to another. Of course the di-graph could be seen as a function as well, mapping a "path" of nodes to the value of the node.

Combining these very conceptually simple concepts of: string (of data), graph (for navigation), and function (mapping) with data is so intuitive for the human brain that I would guess that if you put these concepts together into some sort of web of information, it just might catch on in a world-wide fashion.

smiles. --dawn Received on Thu May 06 2004 - 19:52:17 CEST

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