public static function markProcessed($id, $relationship, $hash)
 {
     if (!is_string($relationship) || !is_string($hash) || !is_string($id) || !$id || !$hash || !$relationship) {
         $this->raiseError("bad parameters");
         return null;
     }
     if (self::$mark_stmt === null) {
         $db = mdb2::singleton();
         self::$mark_stmt = $db->prepare("INSERT INTO form_relationship_importer (id,relationship,hash) VALUES (?, ?, ?)", array('text', 'text', 'text'), MDB2_PREPARE_MANIP);
         if (I2CE::pearError(self::$mark_stmt, "Could not prepare mark statement")) {
             return null;
         }
     }
     if (!self::$mark_stmt) {
         return null;
     }
     return !I2CE::pearError(self::$mark_stmt->execute(array($id, $relationship, $hash)), "Could not mark processed");
 }