assign $_session var from object - php

Question

This is a login script I am working on; It uses mysqli (I know it is not as secure as PDO)
After running the MySQL query I am fetch_object(). I am then assinging $_session to hold the user ID and email. $_SESSION['uid'] = $user->ID works but not $_SESSION['uemail'] = $user->email. Could this be because of email is stored in the object $user? Do I have to convert it somehow?
email is store ass a varchar(255) in the database ID is a int(11).
<?php
include_once("config.php");
$username = $_POST['username'];
$password = sha1($_POST['password']);
$query = "SELECT ID FROM user WHERE username = '$username' AND password = '$password' LIMIT 1";
if ($result = $db->query($query)) {
while ($user = $result->fetch_object()) {
$_SESSION['uid'] = $user->ID;
$_SESSION['uemail'] = $user->email ;
header("Location: index.php");
//exit();
}
}else {
echo "Invalid login information. Please return to the previous page.";
//exit();
}
//var_dump(get_object_vars($result));
//$db->close();
?>
Thanks in advance.

Answer 1

Comment to answer:
You need to select the column(s) for which you are querying for:
SELECT ID, email FROM ...
which is why $_SESSION['uemail'] = $user->email ; is failing.
Either choose the specific column(s) in question, or a SELECT * would also work.
However and it's been said before, that using * isn't suggested, therefore select the actual column(s).

Answer 2

you are not selecting the email column from the database.
Try:
$query = "SELECT ID, email FROM user WHERE username = '$username' AND password = '$password' LIMIT 1";