try {    $dsn = "mysql:host=127.0.0.1;port=3306;dbname=dab";     $pdo = new PDO($dsn, ‘root‘, ‘‘);    $pdo -> setAttribute(PDO::ATTR_AUTOCOMMIT, false);    $pdo -> beginTransaction();    $sql = "update DAB_NTOS_ADMIN set name = :name where id = :id";    $sth = $pdo->prepare($sql);    $sth ->bindValue(‘:name‘, ‘KILL‘);    $sth ->bindValue(‘:id‘, 3);    $flag = $sth-> execute(); // true or false    echo $flag;    $pdo -> commit();} catch (Exception $e) {    if ($pdo) $pdo -> rollBack();} finally {     $pdo = null;}