> -----Original Message-----
> From: Firebird-general@yahoogroups.com
> [mailto:Firebird-general@yahoogroups.com] On Behalf Of Ann W. Harrison
> Sent: Lunes, 18 de Octubre de 2010 13:47
> >
> > Not sure I understand the question completely, but wouldn't a
> > DBMS that allows deferred constraints need to do exactly that?
>
>
> Actually, not exactly. The better way to handle deferred constraints
> is to perform the constraint check immediately, and retain only the
> failures, then recheck the failures on commit. Some - in a properly
> designed system all - of the failures will be corrected. There's
> no reason to recheck all the actions of the transaction.

And isn't there the possibility that a constraint that was validated
(accepted) immediately, would fail if run when all actions have been done
and commit is executed?

C.