public static function addnewAttributeFields(array $tokenTable, array $missingFields)
    {
        if (! isset($tokenTable['participant_id'])) {
            $missingFields['participant_id'] = "ADD participant_id varchar(50) CHARACTER SET 'utf8' COLLATE 'utf8_general_ci' NOT NULL";
        }
        if (! isset($tokenTable['blacklisted'])) {
            $missingFields['blacklisted'] = "ADD blacklisted varchar(17) CHARACTER SET 'utf8' COLLATE 'utf8_general_ci' NOT NULL";
        }

        return $missingFields;
    }