login

if ($result->num_rows > 0)  {
    // output data of each row

    // using loop we are getting following information
    $user_id="";
    $email="";
    $username="";
    while($row = $result->fetch_assoc()) {
          $user_id=$row["user_id"];
          $email=$row["email"];
          $username=$row["username"];
    }


    $_SESSION['user_id'] = $user_id;
    $_SESSION['email'] = $email;
    $_SESSION['username'] = $username;
    $_SESSION['flag'] = true;

    header("location: home.php");

  }