Re: Proposal : Parallel Merge Join

On Tue, Mar 7, 2017 at 11:38 AM, Dilip Kumar <dilipbalaut(at)gmail(dot)com> wrote:
> On Tue, Mar 7, 2017 at 7:47 PM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>> You're right to be confused, because that seems to be a bug in the
>> existing code. There seems to be no guarantee that the cheapest
>> parallel-safe path will be in the cheapest_parameterized_paths list.
>> I'll go fix that.
>
> Okay, Done the simmilar changes in sort_inner_and_outer as well.
>>
>> As a matter of style, when testing a value of type "bool", write if
>> (x) or if (!x). When testing a variable of some other type, say int,
>> write if (x == 0) or if (x != 0) or whatever.
>
> Done
>
> Apart from this, there was one problem in match_unsorted_outer (in
> v10), Basically, if inner_cheapest_total was not parallel_safe then I
> was always getting parallel safe inner. But, we should not do anything
> if jointype was JOIN_UNIQUE_INNER, so fixed that also.

This version looks fine to me, so committed.

--
Robert Haas
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