Re: ERROR: ORDER/GROUP BY expression not found in targetlist

Поиск
Список
Период
Сортировка
От Amit Kapila
Тема Re: ERROR: ORDER/GROUP BY expression not found in targetlist
Дата
Msg-id CAA4eK1+yGs-onuJDy+TTqnrnT0hty_QQPC1GipS+ce-W3872QQ@mail.gmail.com
обсуждение исходный текст
Ответ на Re: ERROR: ORDER/GROUP BY expression not found in targetlist  (Tom Lane <tgl@sss.pgh.pa.us>)
Список pgsql-hackers
On Tue, Jun 14, 2016 at 2:16 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>
> Robert Haas <robertmhaas@gmail.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.
>

Won't the patch as written will allow parallel-restricted things to be pushed to workers for UNION ALL kind of queries?

Explain verbose Select * from (SELECT c1+1 FROM t1 UNION ALL SELECT c1+1 FROM t2 where c1 < 10) ss(a);

In above kind of queries, set_rel_consider_parallel() might set consider_parallel as true for rel, but later in set_append_rel_size(), it might pull some unsafe clauses in target of childrel.   Basically, I am wondering about the same problem as we discussed here [1].



With Regards,
Amit Kapila.
EnterpriseDB: http://www.enterprisedb.com

В списке pgsql-hackers по дате отправления:

Предыдущее
От: Robert Haas
Дата:
Сообщение: Re: Reviewing freeze map code
Следующее
От: Bernd Helmle
Дата:
Сообщение: Re: Using FDW AddForeignUpdateTargets for a hidden pseudo-column