Re: SUPPORT FOR DECLARATIVE TRANSITION CONSTRAINTS

On Sep 28, 12:34 pm, Cimode <cim..._at_hotmail.com> wrote:
> On 28 sep, 17:20, Erwin <e.sm..._at_myonline.be> wrote:
>
> > On 28 sep, 16:05, Brian <br..._at_selzer-software.com> wrote:
>
> > > No.  It isn't.  Only transition constraints can prevent a user from
> > > rewriting history.  All a user needs to do to subvert any state
> > > constraint that involves temporal attributes is to replace the history
> > > of the object under consideration.
> > > - Tekst uit oorspronkelijk bericht weergeven -
>
> > All a user needs to do to subvert your stupid UPDATE transition
> > constraints is not issue an UPDATE, but a DELETE+INSERT multiple
> > assignment instead.
>
> Quite frankly I am surprised that Brian is still sensitive to the
> amount of unnecessary complexity his insight implies.

Having written many triggers and debugged many more, I can say that it is a lot more complicated to implement transition constraints procedurally. Morons will write triggers under the assumption that updates affect only one row at a time, and since the application they're writing doesn't issue updates that affect more than one row at a time, they think everything is fine. Later on, someone else's app issues a set based update and either the trigger bombs, or worse yet, it fails to enforce the constraint it was supposed to implement. Received on Tue Sep 28 2010 - 21:52:51 CEST