Re: sql views for denormalizing

From: dawn <dawnwolthuis_at_gmail.com>
Date: 29 Jul 2005 20:36:31 -0700
Message-ID: <1122694591.679768.17820_at_g49g2000cwa.googlegroups.com>


oops, thought I'd correct typo in subject line. dawn wrote:
> This is another question on the topic about which I have been most
> perplexed -- 1NF.
>
> Because we want to report against or view data potentially in a
> different way than the implementation data model (aka physical model),
> we have views. Although we put our base relations into nth normal
> form, we don't have such rules for the view.
>
> Since my interest is in the interface between developer and dbms, the
> view might be the area where the RM would have me focus (ignoring
> practical issues in working with views such as performance issues).
>
> IF I am writing a s/w app with a browser user interface showing and
> accepting data values that are laid out in a particular order on the
> screen, each with a label, then it might make sense to write a view
> that matches this web page. I could write a view of the data that
> joins, projects and restricts so it includes the desired.
>
> Does this view need to be in 5NF? No. 4NF? No. BCNF? No. 2NF? No. 1NF?
> Yes.
>
> That's where I get messed up because instead of just showing the view,
> I have to massage that view simply because one of the attributes on the
> page has cardinality greater than 1.
>
> If the view is supposed to be the view of the data, then why do we have
> this 1NF restriction when we don't care about the other NF's in a view?
>
> Thanks in advance for your help. --dawn
Received on Sat Jul 30 2005 - 05:36:31 CEST

Original text of this message