Per-statement Triggers (was Re: Proposal: real procedures again (8.4))

On Tue, Oct 30, 2007 at 11:33:19AM -0300, Alvaro Herrera wrote:
> James Mansion wrote:
> > Josh Berkus wrote:
> >> Not only would they be generally useful for SP programming, but
> >> multisets would eliminate one of the big hurdles in re-writing
> >> T-SQL stored procedures in PG, and thus make it easier to port
> >> from SQL Server. You don't hear a lot of demand for multisets on
> >> the mailing lists because we're not getting those SQL Server /
> >> Sybase crossovers now.
> >>
> > Its true that multiple result sets are a big deal with T-SQL
> > programming: but I think you'll also need to provide a way for the
> > locking model to behave in a similar way and also very importantly
> > to be able to emulate the after-statement triggers view of new and
> > old images.
>
> I don't think we need to (or, for that matter, are able to) change
> the locking model, but the NEW and OLD views of for-statement
> triggers should be just a SMOP.

Having NEW and OLD views of per-statement triggers would be a Very
Nice Feature(TM) independent of stored procedures. For one thing, it
would make certain kinds of replication trivial.

Cheers,
David.
--
David Fetter <david(at)fetter(dot)org> http://fetter.org/
Phone: +1 415 235 3778 AIM: dfetter666 Yahoo!: dfetter
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