public static String getTag(String UUID) {
        try {
            PreparedStatement st = MySqlHub.con.prepareStatement("SELECT * FROM Tag_data WHERE UUID = ?");
            st.setString(1, UUID);
            ResultSet rs = st.executeQuery();
            while (rs.next()) {
                return rs.getString("Tag");
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return null;
    }

    public static String getUUID(String nick) {
        try {
            PreparedStatement st = MySqlHub.con.prepareStatement("SELECT * FROM Login_data WHERE Nick = ?");
            st.setString(1, nick);
            ResultSet rs = st.executeQuery();
            while (rs.next()) {
                return rs.getString("UUID");
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return null;
    }