Re: Order & meaning in a proposition

On Tue, 6 Apr 2004 13:32:28 -0500, "Dawn M. Wolthuis" <dwolt_at_tincat-group.com> wrote:

>"Lemming" <thiswillbounce_at_bumblbee.demon.co.uk> wrote in message
>news:3cs5701a7v0onhm11khmcjf154qakn6vk6_at_4ax.com...

>> I'm curious what modelling methods retain sufficient information that
>> such nuances are captured in the final model. Do any such methods
>> exist?
>
>I'll take that bait --

I'm sory, I wasn't baiting anyone, it was a genuine question.

>if one were to model data as if for an XML document,
>for example, then you would not have to put the data in 1NF and could retain
>"multivalues" in your model.

An XML document isn't a method, it's an outcome; A particular implementation for the expression and presentation of aspects of a model.

>First normal form is perhaps the most obvious
>way thast the relational model loses such information (as ordering) when
>modeling propositions by splitting them into so many propositions.

1NF does indeed remove ordering information, unless you put it back (if it's important) within the data itself. But I thought the discussion was about retaining information which may not be considered important at the time of modelling, but nevertheless may be inferred from the statements from which the model is constructed.

>This is
>the same way we modeled data in the 70's (we as a profession) when storing
>it in indexed sequential files with tables permitted as fields in records.

I wasn't around in the 70's, so I don't remember this -- I recall that much of what I was doing in the 80's in COBOL with hierarchical databases using flat files was still by and large using normalised data structures.

>It is the same way data is modeled in PICK and pretty much every data model,
>I suspect, other than relational. So, start by tossing out 1NF and that
>will make a big difference in this area in my opinion. Cheers! --dawn

I don't understand how "tossing out 1NF" offers any gains in capturing nuances of meaning which are not ultimately modelled.

Not being familiar with PICK (although I do remember hearing about it all those years ago) I have to ask how a PICK database is structured, and what advantages that structure has over a relational structure.

Lemming

-- 
Curiosity *may* have killed Schrodinger's cat.