Message-ID: <699e79d831276054266cb2475e072df18d081cf8.camel@j-davis.com>
Subject: Re: Statistics Import and Export
From: Jeff Davis <pgsql@j-davis.com>
To: Corey Huinker <corey.huinker@gmail.com>
Cc: Bruce Momjian <bruce@momjian.us>, jian he <jian.universality@gmail.com>,
  Matthias van de Meent <boekewurm+postgres@gmail.com>, Tom Lane
 <tgl@sss.pgh.pa.us>, Nathan Bossart <nathandbossart@gmail.com>,  Magnus
 Hagander <magnus@hagander.net>, Stephen Frost <sfrost@snowman.net>,
 Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>, Peter Smith
 <smithpb2250@gmail.com>,  PostgreSQL Hackers
 <pgsql-hackers@lists.postgresql.org>, alvherre@alvh.no-ip.org
Date: Fri, 20 Dec 2024 16:16:45 -0800
In-Reply-To: <57990731eb9f5563f83e611a2493a95b1a7d819e.camel@j-davis.com>
References: 
	<CADkLM=eu72o_=s2ARNe8yB-16AUm+_iU0tq_ALeeUUxCCqJkOQ@mail.gmail.com>
	 <11bb2c7403d4a7421fe8b09df6737aa83976266e.camel@j-davis.com>
	 <CACJufxHrJb3L66kzYWeFvN_7RNROaHKUo_JuXK6B64c+TkWOhA@mail.gmail.com>
	 <CADkLM=edhVxHr5OGZHnUeoMkjFYNpE==puOKbB1E_7j1=QsbBw@mail.gmail.com>
	 <CACJufxGmdV-9c7M_fs-2mGBMj1XiVqdOkW0NvibmpBJqedo1uQ@mail.gmail.com>
	 <CADkLM=eErgzn7ECDpwFcptJKOk9SxZEk5Pot4d94eVTZsvj3gw@mail.gmail.com>
	 <be7de51af6e969d501f69426c7137af6bde17fdc.camel@j-davis.com>
	 <CADkLM=eSnbrOPfof8JeSZriFXnqpYcyRw8-WhL5nesbkduDdUQ@mail.gmail.com>
	 <CADkLM=fR7TwH0cLREQkf5_=KLcOYVxJw0Km0i5MpaWeuDwVo6g@mail.gmail.com>
	 <CADkLM=fBaHichB7oS=LZNfTpGHSOTO44OKR28BwNmwu+9PicOg@mail.gmail.com>
	 <ZzuZzDMxe3ClqAgF@momjian.us>
	 <CADkLM=cxNaU3O40Y5zGARJBWm-uAvb2hvgZxd=tOu-zTsrHpkQ@mail.gmail.com>
	 <5d3a24216d15ce8a50d0fc085a13a410202014ca.camel@j-davis.com>
	 <CADkLM=fcAneLoFrd41zdxm_1mMZz+wTp5gLJ=Av5JtBi5cBnDQ@mail.gmail.com>
	 <c2bc08dfec336c03f7a7165d1347e2b52cf98b17.camel@j-davis.com>
	 <CADkLM=fyJ-Y-DNk1aW09btZYdXDXS79xT8oFPTQ6sspWHaqdog@mail.gmail.com>
	 <3bd40d2c686608196b8e04c2aaac9c57c447aae6.camel@j-davis.com>
	 <CADkLM=cWc+Zbjnpew9sg346DdRQJj8OSvZjg4fwvpLH10EViJQ@mail.gmail.com>
	 <CADkLM=eD=k5WFsWK4pCm5j3LjHN7KYj+0USz8L-dN9xO0J2UFQ@mail.gmail.com>
	 <57990731eb9f5563f83e611a2493a95b1a7d819e.camel@j-davis.com>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
User-Agent: Evolution 3.44.4-0ubuntu2 
MIME-Version: 1.0
Archived-At: <https://www.postgresql.org/message-id/699e79d831276054266cb2475e072df18d081cf8.camel%40j-davis.com>
Precedence: bulk

On Thu, 2024-12-19 at 21:23 -0800, Jeff Davis wrote:
> > 0001-0005 - changes to pg_dump/pg_upgrade
>=20
> Attached is a version 36j...

The testing can use some work here. I noticed that if I take out the
stats entirely, the tests still pass, because pg_upgrade still gets the
same before/after result.

Also, we need some testing of the output and ordering of pg_dump.
Granted, in most cases problems would result in errors during the
reload. But we have those tests for other kinds of objects, so we
should have the tests for stats, too.

I like the description "STATISTICS DATA" because it differentiates from
the extended stats definitions. It might be worth differentiating
between "RELATION STATISTICS DATA" and "ATTRIBUTE STATISTICS DATA" but
I'm not sure if there's value in that.

But how did you determine what to use for the .tag and prefix? In the
output, it uses the form:

  Name: STATISTICS DATA <name>; Type: STATISTICS DATA; ...

Should that be:

  Name: <name>; Type: STATISTICS DATA; ...

Or:

  Data for Name: ...; Name: ...; Type: STATISTICS DATA; ...

Or:

  Statistics for Name: ...; Name: ...; Type: STATISTICS DATA; ...

Regards,
	Jeff Davis