Re: Should total_pages be calculated after partition pruning and constraint exclusion?

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: David Rowley <david(dot)rowley(at)2ndquadrant(dot)com>
Cc: PostgreSQL Hackers <pgsql-hackers(at)lists(dot)postgresql(dot)org>
Subject: Re: Should total_pages be calculated after partition pruning and constraint exclusion?
Date: 2018-05-15 23:04:14
Message-ID: 28612.1526425454@sss.pgh.pa.us
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

David Rowley <david(dot)rowley(at)2ndquadrant(dot)com> writes:
> On 16 May 2018 at 08:10, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>> David Rowley <david(dot)rowley(at)2ndquadrant(dot)com> writes:
>> Please add to next CF. It's a bit late to be doing such things in v11,
>> IMO.

> If I do that, it'll go under bug fix.

No, it should go under "planner improvement". If this were a bug fix,
it'd be a candidate for back-patch, which IMO it's not --- if only
because of the risk of plan destabilization. But for a more direct
analogy, if you'd submitted some other improvement in selectivity
or cost estimation, that was not a bug fix in the sense of "corrects
outright wrong answers", would you expect it to escape feature freeze
at this point?

Beta or no beta, there has to be a pretty good argument why changes
should go into v11 and not v12 once we're past feature freeze.

regards, tom lane

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Bruce Momjian 2018-05-15 23:12:23 Re: Postgres 11 release notes
Previous Message David Rowley 2018-05-15 22:51:20 Re: Should total_pages be calculated after partition pruning and constraint exclusion?