Re: BUG #5025: Aggregate function with subquery in 8.3 and 8.4.

Tom Lane wrote:
> Heikki Linnakangas <heikki(dot)linnakangas(at)enterprisedb(dot)com> writes:
> > Tom Lane wrote:
> >> With the fix I was just about to apply, all four cases give the first
> >> set of results. This clearly satisfies the principle of least
> >> astonishment, at least more nearly than what we have; but it equally
> >> clearly is *not* going to restore 8.4 to work just like 8.3.
>
> > Right, 8.3 had the same underlying problem, 8.4 just makes it more
> > visible as it's better at flattening subqueries.
>
> What is interesting is that the CASE in the OP's original submission
> is apparently only there to dodge the visible-since-8.0 version of
> the problem; at least I can't see that it does anything else useful.
> The complaint apparently is not so much that 8.3 was right, as that
> the workaround for its bug stopped working ...

In that light, it probably doesn't make much sense to backport the fix
further back, given that the people (person?) bitten by the bug surely
must already be working around it.

--
Alvaro Herrera http://www.CommandPrompt.com/
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