Re: Triggered Data Change check

Tom Lane wrote:
>
> Hiroshi Inoue <Inoue(at)tpf(dot)co(dot)jp> writes:
> > Strictly speaking MVCC is only for read-only queries.
> > Even under MVCC, update, delete and select .. for update have
> > to see the newest tuples.
>
> True. But my point is that we already have mechanisms to deal with
> that set of issues; the trigger code shouldn't concern itself with
> the problem.

You are saying
> Therefore we don't need any explicit test for triggered data
> change.

ISTM your point is on the following.

> Functions can run new commands that get new command ID numbers within
> the current transaction --- but on return from the function, the current
> command number is restored. I believe rows inserted by such a function
> would look "in the future" to us at the outer command, and would be
> ignored.

My point is why we could ignore the (future) changes.

regards,
Hiroshi Inoue