Re: [PATCH] Push limit to sort through a subquery

Robert Haas <robertmhaas(at)gmail(dot)com> writes:
> On Fri, Aug 25, 2017 at 2:54 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>> Hmm, I'm not sure why SortInstrumentation belongs naturally to
>> tuplesort.h but putting an array of them there would be a "gross
>> abstraction violation". Perhaps it would help to rename
>> struct SharedSortInfo to SortInstrumentationArray, and change its
>> field names to be less specific to the parallel-worker use case?

> What other use case could there be? I think an array of
> SortInstrumentation objects intended to be stored in DSM is fairly
> clearly a bit of executor-specific machinery and thus properly
> declared along with the node that contains it.

I'm not really convinced, but it's not worth arguing further.

Here's a reviewed version of the second patch. I fixed one bug
(wrong explain group nesting) and made some additional cosmetic
improvements beyond the struct relocation.

regards, tom lane