cedjo on "[Plugin: Participants Database] MySQL connection problems with Participant Database"

I have a similar issue, backend is not listing any record. Message is:

WordPress Unknown column '' in 'order clause' for request SELECT * FROM wp_participants_database ORDER BY LIMIT 0,10 done by do_action('base-de-participants_page_participants-database-list_participants'), call_user_func_array, PDb_List_Admin::initialize, referer: http://www.hcv-moju.ch/wp-admin/admin.php?page=participants-database-list_participants

wordpress 3.9