public function install_from_xmldb_structure($xmldb_structure) {

        if (!$sqlarr = $this->generator->getCreateStructureSQL($xmldb_structure)) {
            return; // nothing to do
        }

        $tablenames = array();
        foreach ($xmldb_structure as $xmldb_table) {
            if ($xmldb_table instanceof xmldb_table) {
                $tablenames[] = $xmldb_table->getName();
            }
        }
        $this->execute_sql_arr($sqlarr, $tablenames);
    }