fixing subplan/subquery confusion

On Sun, Jun 26, 2016 at 10:39 PM, Noah Misch <noah(at)leadboat(dot)com> wrote:
> On Mon, Jun 13, 2016 at 04:46:19PM -0400, Tom Lane wrote:
>> Robert Haas <robertmhaas(at)gmail(dot)com> writes:
>> > In practice, we don't yet have the ability for
>> > parallel-safe paths from subqueries to affect planning at higher query
>> > levels, but that's because the pathification stuff landed too late in
>> > the cycle for me to fully react to it.
>>
>> I wonder if that's not just from confusion between subplans and
>> subqueries. I don't believe any of the claims made in the comment
>> adjusted in the patch below (other than "Subplans currently aren't passed
>> to workers", which is true but irrelevant). Nested Gather nodes is
>> something that you would need, and already have, a defense for anyway.
>
> [Action required within 72 hours. This is a generic notification.]
>
> The above-described topic is currently a PostgreSQL 9.6 open item ("fix
> possible confusion between subqueries and subplans"). Robert, since you
> committed the patch believed to have created it, you own this open item. If
> some other commit is more relevant or if this does not belong as a 9.6 open
> item, please let us know. Otherwise, please observe the policy on open item
> ownership[1] and send a status update within 72 hours of this message.
> Include a date for your subsequent status update. Testers may discover new
> open items at any time, and I want to plan to get them all fixed well in
> advance of shipping 9.6rc1. Consequently, I will appreciate your efforts
> toward speedy resolution. Thanks.

This open item comes with a patch submitted by Tom Lane. If Tom wants
me to review and (if no problems are found) commit that patch to
resolve this open item, I'm willing to do that. But generally I don't
commit patches submitted by other committers unless that person and I
have agreed on it in advance, which is not currently the case here.

Tom, do you want to commit this, or do you want me to handle it, or
something else?

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
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