Re: Proposal : Parallel Merge Join

On Fri, Feb 24, 2017 at 4:49 PM, Dilip Kumar <dilipbalaut(at)gmail(dot)com> wrote:
> On Fri, Feb 24, 2017 at 3:04 PM, Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:
>> What advantage do you see for considering such a path when the cost of
>> innerpath is more than cheapest_total_inner? Remember the more paths
>> we try to consider, the more time we spend in the planner. By any
>> chance are you able to generate any query where it will give benefit
>> by considering costlier innerpath?
>
> Changed
>

It seems you have forgotten to change in the below check:

+ if (innerpath != NULL &&
+ innerpath->parallel_safe &&
+ (cheapest_startup_inner == NULL ||
+ cheapest_startup_inner->parallel_safe == false ||
+ compare_path_costs(innerpath, cheapest_startup_inner,
+ STARTUP_COST) < 0))

+ /* Found a cheap (or even-cheaper) sorted parallel safer path */

typo
/safer/safe

Note - Change the patch status in CF app (to Needs Review) whenever
you post a new patch. I could see that your other patch also needs a
similar update in CF app.

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