pg.ddx.io  pgsql-hackers@postgresql.org mailing list archive  

help / color / mirror / Atom feed
From: Dmitry Dolgov <9erthalion6@gmail.com>
To: Pavel Borisov <pashkin.elfe@gmail.com>
Cc: Tomas Vondra <tomas.vondra@2ndquadrant.com>
Cc: Teodor Sigaev <teodor@sigaev.ru>
Cc: Gavin Flower <GavinFlower@archidevsys.co.nz>
Cc: Andres Freund <andres@anarazel.de>
Cc: Michael Paquier <michael@paquier.xyz>
Cc: PostgreSQL Developers <pgsql-hackers@lists.postgresql.org>
Subject: Re: POC: GROUP BY optimization
Date: Mon, 26 Oct 2020 11:40:40 +0100
Message-ID: <20201026104040.6bigvej6f55vjvgp@localhost> (raw)
In-Reply-To: <CALT9ZEF8FUZoijXnFsDXNgqbSHFzaCU2q0cmJFnZ4z2wNZO98w@mail.gmail.com>
References: <CA+q6zcVfsx_YuETPmjkNq-1=kJCS5JuShrL2ZNzm_HRVZ-tiYg@mail.gmail.com>
	<20190409152100.5q25whnxs27zws5m@development>
	<CA+q6zcVRrd-z4YZ4M43ccst7aGL9==w5r1fionRWhP9ot6mybQ@mail.gmail.com>
	<20190503215510.bcr5ycszntqg65tw@development>
	<CA+q6zcVjCVkAhoLD6rjDoPGdfWDjQLD=N2tvfH1yU+Eq+iby9w@mail.gmail.com>
	<20190524225725.embuha33qvc5avz3@development>
	<20200514235220.xewrrwjvatxzn3g6@development>
	<CALT9ZEFU60nW9TJqHUs9Ex_tqv__7t=jfF4Q=iwwxJTO0PY7Rg@mail.gmail.com>
	<20201026085721.g6h5xljxvodnmk34@localhost>
	<CALT9ZEF8FUZoijXnFsDXNgqbSHFzaCU2q0cmJFnZ4z2wNZO98w@mail.gmail.com>

> On Mon, Oct 26, 2020 at 01:28:59PM +0400, Pavel Borisov wrote:
> > Thanks for your interest! FYI there is a new thread about this topic [1]
> > with the next version of the patch and more commentaries (I've created
> > it for visibility purposes, but probably it also created some confusion,
> > sorry for that).
> >
> > Thanks!
>
> I made a very quick look at your updates and noticed that it is intended to
> be simple and some parts of the code are removed as they have little test
> coverage. I'd propose vice versa to increase test coverage to enjoy more
> precise cost calculation and probably partial grouping.
>
> Or maybe it's worth to benchmark both patches and then re-decide what we
> want more to have a more complicated or a simpler version.
>
> Good to know that this feature is not stuck anymore and we have more than
> one proposal.
> Thanks!

Just to clarify, the patch that I've posted in another thread mentioned
above is not an alternative proposal, but a development of the same
patch I had posted in this thread. As mentioned in [1], reduce of
functionality is an attempt to reduce the scope, and as soon as the base
functionality looks good enough it will be returned back.

[1]: https://www.postgresql.org/message-id/flat/CA%2Bq6zcW_4o2NC0zutLkOJPsFt80megSpX_dVRo6GK9PC-Jx_Ag%40m...





view thread (171+ messages)  latest in thread

Message-ID: <20201026104040.6bigvej6f55vjvgp@localhost>
Permalink:  ../20201026104040.6bigvej6f55vjvgp@localhost/
Also on:    postgresql.org/message-id/20201026104040.6bigvej6f55vjvgp@localhost

 · 

reply
Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Reply to all the recipients using the --to and --cc options:
  reply via email

  To: pgsql-hackers@postgresql.org
  Cc: 9erthalion6@gmail.com, pashkin.elfe@gmail.com, tomas.vondra@2ndquadrant.com, teodor@sigaev.ru, GavinFlower@archidevsys.co.nz, andres@anarazel.de, michael@paquier.xyz, pgsql-hackers@lists.postgresql.org
  Subject: Re: POC: GROUP BY optimization
  In-Reply-To: <20201026104040.6bigvej6f55vjvgp@localhost>

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox