Comment 243 for bug 883459

the log file is /var/log/mysql/mysqld.err

However, digging deeper, the problem might be related to two instances of mariadb being present.

pgrep -af mysqld yields

2402 /usr/sbin/mysqld --defaults-file=/etc/mysql/my.cnf
2881 /usr/sbin/mysqld --defaults-file=/home/linuxfan/.local/share/akonadi/mysql.conf --datadir=/home/linuxfan/.local/share/akonadi/db_data/ --socket=/run/user/10001/akonadi/mysql.socket --pid-file=/run/user/1000/akonadi/mysql.pid

While /var/log/mysql/mysqld.err is now clear, in

/home/linuxfan/.local/share/akonadi/db_data/mysql.err

I can see two further errors and some warnings:

[ERROR] Can't open and lock privilege tables: Table 'mysql.servers' doesn't exist
 [Warning] Can't open and lock time zone table: Table 'mysql.time_zone_leap_second' doesn't exist trying to live without them
 [Warning] Failed to load slave replication state from table mysql.gtid_slave_pos: 1017: Can't find file: './mysql/' (errno: 2 "No such file or directory")
 [Note] Reading of all Master_info entries succeeded
 [Note] Added new Master_info '' to hash table
 [Note] /usr/sbin/mysqld: ready for connections.
Version: '10.4.12-MariaDB' socket: '/run/user/1000/akonadi/mysql.socket' port: 0 Source distribution
[ERROR] InnoDB: Table `mysql`.`innodb_table_stats` not found.

what is more important, I believe, is that akonadi seems to start the second mysql instance but some of the data is actually going to my main mysql server instead and its data directory /home/mysql_data/ while other parts are ending up in the akonadi-instance of mysql.

After disabling the stand-alone server, I found that ~/.config/akonadi/akonadiserverrc

still contained the line

Options="UNIX_SOCKET=/var/run/mysql/mysqld.socket"

pointing to the main server socket. Clearing this up, everything seems to end up in the akonadi-version of mysql (with the above warnings/errors, not sure what that means). I am unsure, why some of the data still went to the akonadi-version of mysql, though.

From my point of view, I seem to have had some mess in the config files as I have been dragging/upgrading my /home/ directory with me since 1997 .... (and yes, I have been using KDE ever since the original beta1)