Re: Database design

mAsterdam <mAsterdam_at_vrijdag.org> wrote:

>Mark Johnson wrote:
>> mAsterdam wrote:
>>>The database way (nothing RM specific here) works ok
>>>for a lot of similar facts (same or similar facttypes).
>>>It doesn't work well for dissimilar facts (a lot of
>>>different facttypes) or facttypes you don't know in advance.

>> Because that latter requires some design, some scheme

>Up to here I get it. Yes.

> > for the tables which are supposed to correct?
> > reflect relations in the RM, correct?

>This I can't parse. What are you saying?

Because that latter requires some design, some scheme for the tables which are supposed to reflect relations in the RM, correct?

That is, the tables are supposed to correspond to relations in RM.

And as you get more deeply committed to that structure, things you didn't anticipate in advance threaten to overwhelm any subsequent modification?

There is a scheme or design to the tables and their interlinking. The more dependent upon and/or complicated that fixed structure becomes, there is the possibility that modification to that structure or design become prohibitive, or at least very much prone to error.

>> And as you
>> get more deeply committed to that structure, things you didn't
>> anticipate in advance threaten to overwhelm any subsequent
>> modification?

>Bad design can be quite costly indeed.

But only to point out that the structure from which RM sought to free people, from COBOL or whatever else, was replaced by another equally inflexible structure. But if one builds a COBOL structure upon it, without the interwoven programming, a hierarchy, then perhaps it becomes more useful, but in a way, and for creating certain problems by that (by violating the fundamentals of RM) which some sought to address by a full/materialized path key.

>> At some point, and I think I agreed with him, it is. The tone is a
>> primitive. It is atomic and indivisible.

>That is one point of view.
>POV 2: Frequency, amplitude envelope, harmonic content, phase.

Domains. Imagine a graph or chart. Interpolation through points. You store the points. But a set of points might itself become a primitive by reference. But the initial set of primitives would have to be treated in another fashion. Maybe 'true' primitives vs. 'combined' primitives. But that's weak. Essentially there are the same, but the initial state items would probably require different handling and reference than anything constructed from them. Again, because it is a practical matter, perhaps any theory must necessarily reflect that, as well. But maybe not. I don't know. Received on Thu Feb 23 2006 - 23:10:26 CET