<h1>Employee listing</h1>  <form method="post" >  <p>Enter Department ID:  <input type="text" name="dept_id" size="4">  <input type="submit" name="submit" value="submit"><p>  </form>     <?php  $hostname = "localhost";  $username = "root";  $password = "secret";  $database = "prod";     if (IsSet ($_POST['submit'])) {          $dbh = new mysqli($hostname, $username, $password, $database);          /* check connection */       if (mysqli_connect_errno()) {            printf("Connect failed: %s\n", mysqli_connect_error());            exit ();       }       $dept_id = $_POST['dept_id'];          if ($result_set = $dbh->query("call employee_list( $dept_id )")) {            print ('<table border="1" width="30%"> <tr> '.                 '<td>Employee_id</td><td>Surname</td><td>Firstname</td></tr>');            while ($row = $result_set->fetch_object()) {                 printf("<tr><td>%s</td><td>%s</td><td>%s</td></tr>\n",                        $row->employee_id, $row->surname, $row->firstname);            }       } else {            printf("<p>Error:%d (%s) %s\n", mysqli_errno($dbh),                   mysqli_sqlstate($dbh), mysqli_error($dbh));       }       print ("</table> ");       $dbh->close();  }  ?>