<?php
include "../database.php";
session_start();

$email = $_POST["email"];

$sql_update = "UPDATE users SET email='$email' WHERE id=".$_SESSION["id"]."";
if ($con->query($sql_update) === TRUE) {
    $_SESSION['email'] = $email;

    echo "ok";
} else {
    echo "error";
}

$con->close();