Re: Multi Valued Interface Models?
Date: Fri, 10 Feb 2006 11:21:02 +0200
Message-ID: <dshlu0$fu1$1_at_emma.aioe.org>
"dawn" <dawnwolthuis_at_gmail.com> wrote in message
news:1139520675.770994.71440_at_o13g2000cwo.googlegroups.com...
>
> Marshall Spight wrote:
> > dawn wrote:
> > > ... separate yourself from thinking about the data model for the
> > > database (that is the model of the interface to the database) and
focus
> > > on the data model of the interface to the user. It simply is not
> > > possible for the RM to be the data model for that interface.
> >
> > Can you say why? I read your blog posts, and I didn't see any
> > justification
> > for this statement. Your example UI model wasn't very enlightening,
> > either.
> I thought I said why. If you take an implementation of the RM into a
> language, such as SQL (or some perfect version thereof), you cannot
> have a view of data in that language that is the data interface of this
> UI.
When someone is designing a relational/sql database for something among other things he/she is designing a schema not just a single SQL VIEW. I thought you knew that because I told you that before.
> While you can unnormalize data for SQL views in other ways, you
> cannot get them out of 1NF. An arbitrary user interface is not a 1NF
> view. This does not mean that your data cannot be stored in a database
> where the interface to the database is RM, but that the data model of
> the UI cannot be the RM.
Why unnormalizing the data ? Having it in a normal form would do magic.
> > In any event, I am certain that the "not possible" part of the above
> > statement
> > won't hold up, because the RM can model any concrete type, even if
> > restricted to 1NF.
> How would you model the user interface (not some database related to
> it) in the example given using a language that implements the RM?
You have not given the specifications for the user interface.
> > I'm not saying "convenient" necessarily, just
> > possible.
> Are you talking about adding list types to the RM?
Who said the RM and list types are mutually exclusive ? :-) Received on Fri Feb 10 2006 - 10:21:02 CET