致命错误：调用未定义的方法mysqli_stmt :: query（）

Hey guys, can any of you find out why I'm getting the above error?

$mysqli=new mysqli("localhost", "***", "***","***") or die($mysqli->connect_error);


              function checklogin($username, $password){
                global $mysqli;


                $result = $mysqli->prepare("SELECT * FROM users WHERE username = ?");
                $result->bind_param("s", $username);
                $result->query();

Calling $mysqli->prepare() will return an instance of MySQLi_STMT, but the MySQLi_STMT class doesn't have a query() method. Perhaps you meant execute()?