public function create($tracker_id, $submitted_by, $use_artifact_permissions)
 {
     $tracker_id = $this->da->escapeInt($tracker_id);
     $use_artifact_permissions = $this->da->escapeInt($use_artifact_permissions);
     $submitted_on = $this->da->escapeInt($_SERVER['REQUEST_TIME']);
     $submitted_by = $this->da->escapeInt($submitted_by);
     $id_sharing = new TrackerIdSharingDao();
     if ($id = $id_sharing->generateArtifactId()) {
         $priority_dao = new Tracker_Artifact_PriorityDao();
         if ($priority_dao->putArtifactAtTheEnd($id)) {
             $sql = "INSERT INTO {$this->table_name}\n                        (id, tracker_id, submitted_by, submitted_on, use_artifact_permissions)\n                        VALUES ({$id}, {$tracker_id}, {$submitted_by}, {$submitted_on}, {$use_artifact_permissions})";
             if ($this->update($sql)) {
                 return $id;
             }
         }
     }
     return false;
 }
 public function putArtifactAtTheEnd($artifact_id)
 {
     return $this->priority_dao->putArtifactAtTheEnd($artifact_id);
 }