Update Data in database using PHP with practical?

Code -: 

• index.php

• <?php

• 
  

• $hostname = 'localhost';

• $username = 'root';

• $password = '';

• $databasename = 'testing';

• 
  

• $username1 = "master-tech";

• $password1 = "123";

• 
  

• //password encrypt 

• $password1 = md5($password1);

• 
  

• $u_name = 'hello908';

• 
  

• $master = mysqli_connect($hostname, $username, $password, $databasename); //database conneciton

• 
  

• if($master) {

• echo "connection is established!..";

• //insert data

• $query = "UPDATE `login` SET `username`= '$u_name' WHERE id=6";

• //execute

• $run = mysqli_query($master, $query);

• if($run) {

• echo "<br>update data";

• }

• else{

• echo "<br>no data update";

• }

• 
  

• }

• else {

• echo "connection is not established!..";

• }

• 
  

• 
  

• 
  

• ?>