On Thu, 2004-08-26 at 09:08, Gaetano Mendola wrote:
> Robert Treat wrote:
>
> > On Thu, 2004-08-26 at 04:23, Gaetano Mendola wrote:
> >
> >>Tom Lane wrote:
> >>
> >> > Stephan Szabo <sszabo@megazone.bigpanda.com> writes:
> >> >
> >> >>I believe it sees the one that was valid in the snapshot as of the
> >> >>beginning of the function.
> >> >
> >> >
> >> > Actually, the problem is that it can see *both* that row and the updated
> >> > row; it's a crapshoot which one will be returned by the SELECT INTO.
> >>
> >>Confirmed, if the last select is:
> >>
> >>select count(*) into a from test where id=1;
> >>
> >>this return 2. There is a space for a new bug considering that if the
> >>table have the unique index on id that select must return 1.
> >>
> >> > The reason this can happen is that we're not doing SetQuerySnapshot
> >> > between commands of a plpgsql function. There is discussion going way
> >> > way back about whether we shouldn't do so (see the archives). I think
> >> > the major reason why we have not done it is fear of introducing
> >> > non-backwards-compatible behavior. Seems like 8.0 is exactly the right
> >> > version to consider doing that in.
> >>
> >>If my 2 cents are valid I agree with you, what I don't totally agree is why
> >>consider this bug as a *feature* in previous 8.0 version.
> >>
> >
> > I don't think this was ever considered a feature (at least I never found
> > any evidence of that) but more the concern was that it was "expected
> > behavior" and changing that behavior might toss people into a loop who
> > were expecting it.
>
> Yes, I used the wrong expression is not a feature but a gotcha.
> I fairly trust that someone is currently using this behaviour considering it
> the good expected one.
>
Really? I don't. I do suspect there are people using this behavior
considering it the bad, but expected, one. However if people really do
want this functionality to stay the same, let them speak up via a vote
on the subject.
Robert Treat
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