//query to fetch all users tying to groups
    $query = "  SELECT groupID
                    FROM Users U
                        JOIN
                            Groups_users GU
                                ON
                                    U.userID = GU.userID
                    WHERE
                        U.userID = '$_SESSION[name]';";

    $result = $db->query($query);
    $groups_ids = $result->fetchAll();

    $users_typing=array();

    for($i=0;$i<count($groups_ids);$i++){
        $query = "  SELECT groupID,U.nickname
                        FROM Users U
                            JOIN
                                Groups_users GU
                                    ON
                                        U.userID = GU.userID
                        WHERE
                            GU.is_typing = '1';";
        $result = $db->query($query);
        array_push($users_typing,$result->fetchArray());
    }