<?php
$host = "localhost";
$user = "root";
$password ="";
$database = "crud";
$conn = new mysqli($host, $user, $password);
mysql_select_db($database);

if(isset($_POST['btn-save']))
{
$first_name = $_POST['first_name'];
$last_name = $_POST['last_name'];
$city_name = $_POST['city_name'];
$sql_query ="INSERT INTO users(first_name,last_name,user_city) VALUES('$first_name','$last_name','$city_name')";
  mysql_query($sql_query);
}
?>