Comments - Help me understand mariadb-upgrade
Content reproduced on this site is the property of its respective owners,
and this content is not reviewed in advance by MariaDB. The views, information and opinions
expressed by this content do not necessarily represent those of MariaDB or any other party.
Thank you for your help.
In fact this file is missing. I made a test and deleted the whole "datadir" and started MariaDB. The database was initialized from scratch and "mysql_upgrade_info" is present.
Something is wrong with the backup/restore procedure!
I made my backup and restore with mariadb-backup according to this manual https://mariadb.com/kb/en/incremental-backup-and-restore-with-mariabackup/.
In the "restore" section there is clearly stated "ensure that the datadir is empty" so I deleted the content of /var/lib/mysql and of course the "mysql_upgrade_info" was deleted too.
Obviously "mariadb-backup" did not create this file so either the manual is wrong or some program involved in the restore/startup process should create this "mysql_upgrade_info" file.
Yep, sounds like worthy enhancement. Please create a request on https://jira.mariadb.org