Deleting a database

<?php
$server = 'localhost';
$user = 'root';
$password = '';
$conn = mysqli_connect($server, $user, $password);
if($conn){
$query = "DROP DATABASE `TNW`";
$query_run = mysqli_query($conn, $query);
if($query_run){
echo 'Successfully deleted a Database.';
}else{
echo 'Deleting a database Error.';
}
}else{
echo 'Connection Error';
}
?>