Re: [COMMITTERS] pgsql: Don't generate parallel paths for rels with parallel-restricted

On Fri, Jun 10, 2016 at 8:20 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>
> Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> writes:
> > On Thu, Jun 9, 2016 at 11:38 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> >> Robert Haas <robertmhaas(at)gmail(dot)com> writes:
> >>> Could you answer my question about whether adjust_appendrel_attrs()
> >>> might translate Vars into non-Vars?
>
> >> Yes, absolutely.
>
> > Isn't this true only for UNION ALL cases and not for inheritance child
> > relations (at least that is what seems to be mentioned in comments
> > for translated_vars in AppendRelInfo)?
>
> Correct.
>
> > If that is right, then I think
> > there shouldn't be a problem w.r.t parallel plans even if
> > adjust_appendrel_attrs() translate Vars into non-Vars, because for UNION
> > ALL it seems parent rels rtekind is RTE_SUBQUERY and we consider such
rels
> > as parallel unsafe (see set_rel_consider_parallel()).
>
> Hm, that would explain why you haven't been able to exhibit a bug on HEAD
> as it stands;
>

Right, so I have moved "Failed assertion in parallel worker
(ExecInitSubPlan)" item to CLOSE_WAIT state as I don't think there is any
known pending issue in that item. I have moved it to CLOSE_WAIT state
because we have derived our queries to reproduce the problem based on
original report[1]. If next run of sqlsmith doesn't show any problem in
this context then we will move it to resolved.

[1] - https://www.postgresql.org/message-id/8760use0hl.fsf%40credativ.de

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