Message-ID: <b527f417-b27c-43bb-8623-4c703fc0ad72@dalibo.com>
Date: Mon, 28 Jul 2025 17:09:15 +0200
MIME-Version: 1.0
User-Agent: Mozilla Thunderbird
Subject: Re: vacuumdb changes for stats import/export
To: Nathan Bossart <nathandbossart@gmail.com>
Cc: Corey Huinker <corey.huinker@gmail.com>, Bruce Momjian
 <bruce@momjian.us>, "David G. Johnston" <david.g.johnston@gmail.com>,
 John Naylor <johncnaylorls@gmail.com>,
 Masahiko Sawada <sawada.mshk@gmail.com>, Jeff Davis <pgsql@j-davis.com>,
 jian he <jian.universality@gmail.com>,
 Matthias van de Meent <boekewurm+postgres@gmail.com>,
 Tom Lane <tgl@sss.pgh.pa.us>, 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
References: <Z9R9-mFbxukqKmg4@nathan> <Z9jXuyymBSVDw9pv@nathan>
 <CADkLM=ek625v06WeeOpUNjGnCqyD8pH_0iYcCpg57KP3A8D9qg@mail.gmail.com>
 <Z9nnsPBlBzWxDuLi@nathan> <4b94ca16-7a6d-4581-b2aa-4ea79dbc082a@dalibo.com>
 <aITkuWC4Ww88GsFL@momjian.us>
 <CAKFQuwa2-oW__J7gAcVKgZnx658qBx9GknwL-wqX_0VvDc1EBQ@mail.gmail.com>
 <aIT9HMuQNIFfIlFH@momjian.us>
 <CADkLM=f9eYO_2f2LEf9a2zR_Zw9a4LtVAeqC_TdQEJdTuR-V+Q@mail.gmail.com>
 <8320fa2e-9200-46e2-b905-4a4d84707020@dalibo.com> <aIeNeo-zGgevViNc@nathan>
From: =?UTF-8?Q?Fr=C3=A9d=C3=A9ric_Yhuel?= <frederic.yhuel@dalibo.com>
Content-Language: fr, en-US
Autocrypt: addr=frederic.yhuel@dalibo.com; keydata=
 xjMEXn3bgxYJKwYBBAHaRw8BAQdA6tX5FT/n5ztMWIoBdl6k5avvu65fv6ryfVzIx/aH3V3N
 JEYuIFlodWVsIDxmcmVkZXJpYy55aHVlbEBkYWxpYm8uY29tPsKWBBMWCAA+FiEEi7OTyf6H
 ePS+C6n11XGWhN8zGNUFAmZDVJ8CGwMFCQtfi90FCwkIBwIGFQoJCAsCBBYCAwECHgECF4AA
 CgkQ1XGWhN8zGNV65gEA6o+UrebFjn2CIAOYwP3CiiJugiM5TMH9yJyehQua5ZoA/2ChxiVn
 8OUaAw/ErxJmQi1mSN0tNZBL/KhkUPBDUDQNzjgEXn3bgxIKKwYBBAGXVQEFAQEHQCuh5cLQ
 AtEBXHa2Fmtp0kduBu7msM7qO/gaEcdjFUdiAwEIB8J+BBgWCAAmAhsMFiEEi7OTyf6HePS+
 C6n11XGWhN8zGNUFAmZDVJ8FCQtfi90ACgkQ1XGWhN8zGNWOOAEArSqePBqfd4Kx4ulACaWO
 6fM+XSDfUlBAQXx9rU6DR4MBALwozl9g91tRysim6lKxggvBfp/PvbpTZNrxYLWB2fYP
In-Reply-To: <aIeNeo-zGgevViNc@nathan>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit
Archived-At: 
 <https://www.postgresql.org/message-id/b527f417-b27c-43bb-8623-4c703fc0ad72%40dalibo.com>
Precedence: bulk


On 7/28/25 16:47, Nathan Bossart wrote:
> I can't remember who wrote this line, but it was borrowed from the
> --analyze-in-stages description.  The point is that if you use
> --analyze-in-stages without --missing-stats-only, there will be a period
> where existing statistics will be replaced with ones generated with lower
> statistics targets.

Aha, it makes sense now, thank you!

> Obviously, this wording isn't clear enough.  We might
> need to either remove that sentence or add "When used in conjunction with
> --analyze-in-stages..."

I vote for the second option.