// preparing a temporary table that unions the admin and employee tables
$TMP = "SELECT EMP_ID AS ID, EMP_EMAIL AS EMAIL, 2 AS TYPE FROM employee
                        UNION
                        SELECT ID, EMAIL, 1 AS TYPE FROM admin ";
$result = $con->prepare($TMP);
$result-> execute();
$result-> store_result();
$result-> fetch();

    // preparing select statement for logging in
$stmt = $con->prepare('SELECT `TYPE` FROM `".$result."` WHERE `ID` = ?');
    // Bind parameters (s = string, i = int, b = blob, etc), in our case the username is a string so we use "s"
    $stmt->bind_param('i', $_POST['ID']);
    $stmt->execute();
    // Store the result so we can check if the account exists in the database.
    $stmt->store_result();
    if ($stmt->num_rows > 0) {
    $stmt->bind_result($ID);
    $stmt->fetch();
    }
        if ($stmt['TYPE'] == 1) {
            if ($_POST['ID'] == $ID) {
        // Verification success! User has loggedin!
        // Create sessions so we know the user is logged in, they basically act like cookies but remember the data on the server.
            session_regenerate_id();
            $_SESSION['loggedin'] = TRUE;
            $_SESSION['email'] = $_POST['EMAIL'];
            $_SESSION['id'] = $ID;
            echo 'Welcome ' . $_SESSION['email'] . '!';
        } else {
        echo 'Incorrect password!';
    }
        } else if ($stmt['TYPE'] == 2) {
    if ($_POST['ID'] == $ID) {
        // Verification success! User has loggedin!
        // Create sessions so we know the user is logged in, they basically act like cookies but remember the data on the server.
        session_regenerate_id();
        $_SESSION['loggedin'] = TRUE;
        $_SESSION['email'] = $_POST['EMAIL'];
        $_SESSION['id'] = $ID;
        echo 'Welcome ' . $_SESSION['email'] . '!';
    } else {
        echo 'Incorrect password!';
    }
        }
    $stmt-> close();



$result-> close();
$con-> close();