Re: foundations of relational theory?

Originally posted by Bob Badour

> "byrmol" <member27348_at_dbforums.com> wrote in message

> news:3551203.1067812771_at_dbforums.com"]news:3551203.1067812771_at_d-
> bforums.com[/url]...

> > >

> > > Basically:

> > > * Structure:

> > > All data in D3 is stored as items within files.

> > > Items within these files are divided into sets called
> attributes which

> > > contain one, multiple, or no values.

> > > * Integrity

> > > Can be enforced in multitudinous ways. It is perhaps worth
> noting that

> > > much of what is elsewhere called "data integrity" falls (quite
> rightly

> > > imo) under the heading of "input validation" in Pick
> applications that

> > > run wholly or partly within the DBMS. Pick has full ACID
> compliance

> > > for transaction handling btw.

> > > * Manipulation

> > > What is there to say? You read, write & delete data as you
> need to -

> > > and you need to do much less of it in Pick than with any of
> the

> > > attempts to implement the relational model.

> > >

> > > If you want, as I suspect you might, more in-depth answers
> then can

> > > you point me to a definition of a model with these sub-
> headings that I

> > > can use as a kind of template?

> > >

> > Here is the relational models conformance to a definition of
> a

> > data model.

> > Its general theory is set theory and predicate logic expressed
> as...

> > * Structure - R-tables

> > * Integrity - Domain, attribute, relation, database

> > * Manipulation - R-operations (R-algebra & R-calculus)

> > From your reply I am getting the impression that MV/PICK is not
> a data

> > model at all but simply an application.

>

> A primitive file processor to be exact.

C'mon Bob.

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