Re: Suppressing unused subquery output columns - Mailing list pgsql-hackers

From Tom Lane
Subject Re: Suppressing unused subquery output columns
Date
Msg-id 26238.1402588987@sss.pgh.pa.us
Whole thread Raw
In response to Re: Suppressing unused subquery output columns  (Robert Haas <robertmhaas@gmail.com>)
Responses refactoring allpaths.c (was Re: Suppressing unused subquery output columns)  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
Robert Haas <robertmhaas@gmail.com> writes:
> On Thu, Jun 5, 2014 at 10:27 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> The attached draft patch fixes this by deleting unused output expressions
>> from unflattened subqueries, so that we get:
>> ...
>> I'm not entirely convinced that it's worth the extra planning cycles,
>> though.  Given the small number of complaints to date, it might not
>> be worth doing this.  Thoughts?

> I've encountered this issue before and think it would be great to fix
> it.  I'm not sure precisely how many cycles it's worth paying, but
> definitely more than zero.

We have a couple votes for this patch and no one has spoken against it,
so I'll go ahead and push it into HEAD.
        regards, tom lane



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