Comment # 7 on bug 1200860 from Fabian Vogt

(In reply to Christopher Yeleighton from comment #6)
> The upgrade to from 10.7.3-MariaDB to 10.10.2-MariaDB caused 9���GB of the
> following message to fill the file mysql.err.old, eventually taking up all
> storage space:
> 
> [ERROR] Incorrect definition of table mysql.column_stats: expected column
> 
> This is no way to do business, my good sirs :-(

That's unrelated. MySQL/MariaDB for some reason needs mysql_upgrade to be
called manually and Akonadi doesn't handle that either. So run mysql_upgrade -S
$XDG_RUNTIME_DIR/akonadi/mysql.socket after mariadb version upgrades.