Re: The Theoretical Foundations of the Relational Model

From: Alfredo Novoa <alfredo_at_nospam_ncs.es>
Date: Thu, 04 Jul 2002 21:04:12 GMT
Message-ID: <3d24b7df.3352110_at_newscache4.freenet.de>


On Thu, 04 Jul 2002 11:16:38 +1000, Clifford Heath <cjh_nospam_at_managesoft.com> wrote:

>Alfredo Novoa wrote:
>> > ORM offers the least inflexible method for capturing conceptual designs
>> And what about using text?
>
>I'm not talking about the representation of the design

I am not either. I am talking about using a textual language based on predicate logic for capturing conceptual designs. Of course it is a relational approach.

>, and besides, ORM
>has a textual form. I'm talking about postponing conceptually unimportant
>decisions (mainly the decision about which things should be entities and
>which attributes) until the logical or physical design stage (when this
>decision must be made).

It sounds very interesting. I think I should learn more about ORM.

I have a question. Is ORM well suited to capture things like this?

The stock of an article is the sum of the initial stock plust the sum of purchase invoice lines minus the sum of sale invoice lines, all grouped per lot and warehouse.

It is a very simplified example, but this kind of things are very important for me, and it may be very easily captured with a relational language like Date's Tutorial D.

Alfredo Received on Thu Jul 04 2002 - 23:04:12 CEST

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