getEntityManager(); $existingRelation = $this->findOneBy([ 'attendanceCalendar' => $calendarId, 'group' => $groupId, ]); if (!$existingRelation) { $relation = new CAttendanceCalendarRelGroup(); $relation->setAttendanceCalendar($em->getReference(CAttendanceCalendar::class, $calendarId)); $relation->setGroup($em->getReference(CGroup::class, $groupId)); $em->persist($relation); $em->flush(); } } }