function get_client_id($username) {
//$user = $_SESSION['user'];
//$username = $user['username'];
$db = "";
$query = "
SELECT `client_id` FROM `users`
WHERE `username` = '$username' LIMIT 1
";

try
{

$stmt = $db->prepare($query);
$stmt->execute();
}
catch(PDOException $ex)
{
die("Failed to run query: " . $ex->getMessage());
}


$rows = $stmt->fetchAll();


$client_id = $rows[0]['client_id'];

return ($client_id);
}