PDOException: PDO::__construct(): php_network_getaddresses: getaddrinfo failed: no such host known

php mysql pdo xampp

PHP Snippet 1:

$hostName = "localhost";
$dbName = "test";
$userName = "test";
$password = "test1";
try {
    $pdo = new PDO("mysql:host=$hostName;dbname=$dbName",$userName,$password);
    $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
    echo "Connected successfully"; 
    }
    catch(PDOException $e)
    {
     echo "Connection failed: " . $e->getMessage();
    }