Horton

Re: Stronger safeguard for archive recovery not to miss data

Laurenz Albe <laurenz.albe@cybertec.at>

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From: Laurenz Albe <laurenz.albe@cybertec.at>
To: Fujii Masao <masao.fujii@oss.nttdata.com>, "osumi.takamichi@fujitsu.com" <osumi.takamichi@fujitsu.com>, 'Kyotaro Horiguchi' <horikyota.ntt@gmail.com>
Cc: "david@pgmasters.net" <david@pgmasters.net>, "pgsql-hackers@lists.postgresql.org" <pgsql-hackers@lists.postgresql.org>
Date: 2021-04-02T14:48:55Z
Lists: pgsql-hackers 
On Thu, 2021-04-01 at 17:25 +0900, Fujii Masao wrote:
> Thanks for updating the patch!
> 
> +                                errhint("Use a backup taken after setting wal_level to higher than minimal "
> +                                                "or recover to the point in time before wal_level becomes minimal even though it causes data loss")));
> 
> ISTM that "or recover to the point in time before wal_level was changed
>   to minimal even though it may cause data loss" sounds better. Thought?

I would reduce it to

"Either use a later backup, or recover to a point in time before \"wal_level\" was set to \"minimal\"."

I'd say that we can leave it to the intelligence of the reader to
deduce that recovering to an earlier time means more data loss.

Yours,
Laurenz Albe

Commits

  1. Fix test added by commit 9de9294b0c.

  2. Stop archive recovery if WAL generated with wal_level=minimal is found.