Grzegorz Jaśkiewicz escribió:
> On Wed, Feb 4, 2009 at 9:09 PM, Peter Eisentraut <peter_e@gmx.net> wrote:
> > On Wednesday 04 February 2009 20:36:24 Grzegorz Jaśkiewicz wrote:
> >> I dream about db wide checks on tables, without need to write
> >> expensive triggers.
> >> Basically, something that would run a select query after
> >> insert/update/delete and based on result commit or rollback.
> >> unless there's something like that already in SQL (I am not aware of
> >> all features in sql2008 draft).
> >
> > Sounds like ASSERTION, standard SQL feature. Certainly interesting.
> >
> I was sure something like that existed, but had no idea about name.
> It also shouldn't be very hard to add, me guesses.
A trivial, stupid implementation is perhaps not too difficult. The
problem is getting the smarts right, i.e. an optimized version. You
certainly don't want to be executing a query against a large table for
every INSERT on another one, for example; it's better if if you can
figure out when to skip it.
--
Alvaro Herrera http://www.CommandPrompt.com/
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