Re: Dreaming About Redesigning SQL

"Bob Badour" <bbadour_at_golden.net> wrote in message news:x7udneV85fdKpgiiXTWJhg_at_golden.net...
> "Paul Vernon" <paul.vernon_at_ukk.ibmm.comm> wrote in message
> news:bn31fe$aie$1_at_gazette.almaden.ibm.com...
> > "Lauri Pietarinen" <lauri.pietarinen_at_atbusiness.com> wrote in message
> > news:bmv01r$u69$1_at_nyytiset.pp.htv.fi...
> > > >>Say if you had a large insurance company with, say, 10000 rules,
would
> > > >>it *really* work?
> > > >>
> >
> > Il'd say that would be exactly the kind of application that a pure
> > relational approach would *really* work very well indeed.
> >
> > > >
> > > >Yes, absolutely. It would scale at least as well as it does today. It
> > would
> > > >be more manageable than it is today because the important business
> logic
> > > >would not be scattered among hundreds of applications. It would
easily
> > adapt
> > > >to all situations. Why would it not?
> > > >
> > > >
> > > [snipped]
> > >
> > > That is all very clear, and that is how I have understood the goal.
> > > But, as they say, the devil lies in the details.
> > >
> > > The Versata product has been used to create a fairly large rule-based
> > > application at
> > > American Management Systems. I wonder if anybody knows anything about
> > > this application
> > > .
> > > See this IBM red book:
> > >
> >
>
http://publib-b.boulder.ibm.com/Redbooks.nsf/RedbookAbstracts/sg246510.html?
> Open
> >
> > Can't say I know about that app, but it's statistic of replacing 3.7
> million
> > lines of (COBOL) code with 12,000 business rules is not a bad start to
> what
> > I suspect is possible with relational approaches (i.e. I think I'd be
> > surprised if those 12,000 couldn't be reduced by a factor of 10 in a
purer
> > relational system).

>
> The question is not how few rules one can write, but how few rules the
dbms
> must enforce to ensure consistency. If they wrote 12,000 but the dbms need
> only enforce 1,200, the dbms takes care of the reduction.
>

Humm,.

Well ultimately it's just one rule. One humongous Boolean expression that must always evaluate to TRUE for every valid database value for the given database schema.

I guess that 'number of rules' is nearly as good a measure of inherent complexity as 'number of lines of code'. ;-)

Regards
Paul Vernon
Business Intelligence, IBM Global Services Received on Tue Oct 21 2003 - 17:11:13 CEST