Вывод баланса на php сайте из sql

$table[] = "DROP TABLE IF EXISTS `accounts`"; 
$table[] = "CREATE TABLE `accounts` ( 
`id` int(11) NOT NULL auto_increment, 
`login` varchar(16) NOT NULL, 
`password` varchar(16) NOT NULL, 
`adminlevel` int(15) NOT NULL, 
`balance` int(15) NOT NULL,
`question` varchar(255) NOT NULL, 
`answer` varchar(15) NOT NULL, 
`phone` int(15) NOT NULL, 
`email` varchar(33) NOT NULL, 
PRIMARY KEY (`id`) 
) TYPE=MyISAM /*!40101 DEFAULT CHARACTER SET " . COLLATE . " COLLATE " . COLLATE . "_general_ci */";

SELECT `balance` FROM `accounts` WHERE `id` = 1;

<?php
  session_start();
 
  $login = $_POST['login'];
  $password = $_POST['password'];
  $password = md5($password);
 
  function authUser($login, $password) {
    if (($login == '') && ($password == '')) return false;
    $mysqli = new mysqli('localhost', 'root', '', 'mydb');
    $result_set = $mysqli->query("SELECT `login`, `password`, `id` FROM users WHERE `login` = '$login'");
    $user = $result_set->fetch_assoc();
    $result_set->close();
    $mysqli->close();
    $_SESSION['user_id'] = $user['id'];
    return $password == $user['password'];
  }
 
  $id = $_SESSION['user_id'];
  $mysqli = new mysqli('localhost', 'root', '', 'mydb');
  $result_set = $mysqli->query("SELECT `balance` FROM users WHERE `id` = '$id'");
  $user = $result_set->fetch_assoc();
  $result_set->close();
  $mysqli->close();
  $user_balance = $user['balance']; //баланс юзера
?>