Re: Multiplicity, Change and MV
Date: Tue, 18 Apr 2006 16:38:50 +0300
Message-ID: <e22q3o$760$1_at_emma.aioe.org>
"Bob Badour" <bbadour_at_pei.sympatico.ca> wrote in message
news:eJ51g.61664$VV4.1151927_at_ursa-nb00s0.nbnet.nb.ca...
> x wrote:
>
> > "dawn" <dawnwolthuis_at_gmail.com> wrote in message
> > news:1145292548.823950.44180_at_u72g2000cwu.googlegroups.com...
> >
> >>x wrote:
> >>
> >>>"dawn" <dawnwolthuis_at_gmail.com> wrote in message
> >>>news:1144858576.001309.90750_at_z34g2000cwc.googlegroups.com...
> >>>
> >>>>x wrote:
> >>>>
> >>>>>"B Faux" <nospam_at_nospam.net> wrote in message
> >>>>>news:EvS_f.24004$NS6.8332_at_newssvr30.news.prodigy.com...
> >>>>>
> >
> >
> >>>I wonder if those who use them are confused by them or there are some
> >>>precise definitions of them.
> >>
> >>There are some terms with very precise definitions such as file,
> >>attribute/field, value (on my site in the MultiValue triology,
> >>particularly the Data "flashcards"), but since the model is not aligned
> >>precisely with any single, simple, mathematical model, there is a lot
> >>that is not nearly as precise as a mathematical definition would be.
> >>
> >>Most terms are trivially defined. When an MV person says or writes a
> >>term in English, the meaning is found in an English dictionary. There
> >>is not a big distinction between saying that "Courses have
> >>prerequisites" (conceptual data model) and the correspnoding "Within
> >>each Course we will place a list of Prerequisites" (act of defining a
> >>dictionary). It can be difficult to explain the difference between a
> >>conceptual data model and a logical data model to an MV person. If a
> >>file called Person has a field called FormerNames, that is the
> >>implementation of the conceptual model (coming from the "real world")
> >>where a person might have a list of former names.
> >
> > This might be the reason of programmers productivity.
>
> Human languages are imprecise -- often with multiple possible meanings.
> This leads to frequent misunderstandings, which humans have evolved to
> deal with in a reactionary manner. Human languages are much less
> susceptible to symbolic manipulation, reducing the opportunities to
> increase productivity through automation.
> I fail to see how such an imprecise language could increase
> productivity.
I don't see how but I think is this imprecision what allows for the
expressiveness of human languages.
If you followed the ttm list recently, you might have read a message called
"A Join ambiguity" which I wrote.
> Or are you suggesting that the programmers' productivity
> has been reduced as a result?
Now, because you asked :-) here it is:
- I don't remember why I said that initially. I think it was a reflex :-)
- Now I think it is a double edged sword :-)
> >>Nothing in the application would break if you change the cardinality of
> >>an attribute (although it would be possible to write some code that
> >>would cause it to break, since you can do most anything).
> One should point out to Dawn that we established three years ago that
> her assertion above is patently false. She is a willful ignorant
> interested in nothing more than self-promotion.
Her above assertion could be false, she might be interested in self-promotion, but I think there are not many who can answer her questions in a simple and precise language. Such questions from Fabian Pascal made me think with my own head about relational model. So, you see, in a way they are alike :-)
One thing I don't like is to be spoon fed at this age.
> >>>One RM rule say "no subversion" !
> >
> >
> >>There is most definitely a different sense of what is elegant between
> >>the two worlds. Pick defines elegance almost exclusively in terms of
> >>maintainable code over time that accomplishes what the business needs.
>
> We established three years ago that the meaning of Pick queries change
> subtly with no obvious indication to the user. The fact that Pick people
> believe this makes code mantainable suggests severe cognitive damage.
Ok. Received on Tue Apr 18 2006 - 15:38:50 CEST