Password hashing

<?php
            } else {
                $servername = "198.71.225.55:3306";
                $dbuser = "";
                $dbpw = "";
                $dbname = "heartfx_users";
                $db = new PDO( 'mysql:host=198.71.225.55:3306;dbname=heartfx_users', $dbuser, $dbpw );

                $form = $_POST;
                $firstname = $form['firstname'];
                $lastname = $form['lastname'];
                $username = $form['username'];
                $password = $form['password'];
                $email = $form['email'];

                // Hash a new password for storing in the database.
                $password = password_hash($password, PASSWORD_BCRYPT);


                $sql = "INSERT INTO Users ( firstname, lastname, username, password, email )
                VALUES ( :firstname, :lastname, :username, :password, :email )";

                $query = $db->prepare( $sql );
                $result = $query->execute( array( ':firstname'=>$firstname, ':lastname'=>$lastname, ':username'=>$username, ':password'=>$password, ':email'=>$email ) );
            }
        ?>