/**
 * Executes a SQL statement.
 * This method executes the specified SQL statement using [[db]].
 * @param string $sql the SQL statement to be executed
 * @param array $params input parameters (name => value) for the SQL execution.
 * See [[Command::execute()]] for more details.
 */
    public function execute($sql, $params = [])
{
    echo "    > execute SQL: $sql ...";
    $time = microtime(true);
    $this->db->createCommand($sql)->bindValues($params)->execute();
    echo " done (time: " . sprintf('%.3f', microtime(true) - $time) . "s)\n";
}