Re: Normalization and Derived Information

"Kenneth Downs" <firstinit.lastname_at_lastnameplusfam.net> wrote in message news:soasjc.3is.ln_at_mercury.downsfam.net...
> Dawn M. Wolthuis wrote:
>
> > "Kenneth Downs" <firstinit.lastname_at_lastnameplusfam.net> wrote in
message
> > news:2pf1jc.cgg.ln_at_mercury.downsfam.net...
> >> Laconic2 wrote:
> >>
> >> My current thinking, which I am implementing in my current project, is
to
> >> materialize in the INSERT and UPDATE triggers. This is not to say
there
> >> are not other ways, but in this way the definitions are satisfied
within
> >> the transaction. There will be howls of protest about performance,
but
> >> methinks the CPU time on the server to generate the value is less than
> >> the wire time to send it over from another tier (I could be wrong).
> >
> > I could be missing something, but the only way there would be howls of
> > protest would be if you decided to materialize the values synchronously,
> > right? I can see reasons to update data synchronously, but no reason to
> > maintain materialized derived data while a user waits. Triggering an
> > asynch
> > processes would make more sense, I would think. Again, maybe I'm not
> > understanding either your requirements or your design. Cheers! --dawn
>
> The howls of protest are, as you suspect, over synchronous updates, where
I
> measured performance slowdowns of 20% in that environment. This I judge,
> and emphasis here is on personal judgement, to be far superior to the
> faster transactions, where the users waited days, weeks, and months for
> mistakes to be fixed in the extremely complex house-that-jack-built system
> that attempted to reliably and repeatably derive these values on the fly
at
> extraction time.

These are not the only options. You could update materialized derived data from transactional data asynchronously, while updating the base data synchronously. --dawn

> >
> >> --
> >> Kenneth Downs
> >> Use first initial plus last name at last name plus literal "fam.net" to
> >> email me
>
> --
> Kenneth Downs
> Use first initial plus last name at last name plus literal "fam.net" to
> email me
Received on Mon Oct 04 2004 - 22:44:51 CEST