"SELECT su.seminar_id, IF(s.visible = 0, CONCAT(s.Name, ?), s.Name) AS Name,
                 stm_instance_id,
                 sd1.name AS startsem, IF(duration_time = -1, ?, sd2.name) AS endsem
          FROM seminar_user AS su
          INNER JOIN seminare AS s ON (su.seminar_id = s.Seminar_id)
          INNER JOIN stm_instances_elements AS sie ON (su.seminar_id = sem_id)
          LEFT JOIN semester_data AS sd1 ON (start_time BETWEEN sd1.beginn AND sd1.ende)
          LEFT JOIN semester_data AS sd2 ON (start_time + duration_time BETWEEN sd2.beginn AND sd2.ende)
          WHERE su.user_id = ? AND su.status = 'dozent'"