From KDE UserBase Wiki

    mysqld: unknown variable 'innodb_file_per_table=1'

    If the MySQL server log contains the following error, then your MySQL server was built without the InnoDB support which is required by Akonadi or InnoDB needs to be loaded in your mysql.conf file:

    [ERROR] /usr/libexec/mysqld: unknown variable 'innodb_file_per_table=1'

    [ERROR] Aborting

    Try adding:

    #sql_mode=strict_trans_tables <- Add underneath this line
    plugin_dir=usr/lib/mysql/plugin < - This may be a different path