public Models.DatabaseModel.Bill findBill(int billId) {
        String query = "SELECT `bill`.`billId`, "
                + "     `bill`.`patientId`, "
                + "     `bill`.`dateCreated`, "
                + "     `bill`.`datePaid`, "
                + "     `bill`.`consultationCost` "
                + " FROM `bill` "
                + " WHERE `bill`.`billId` = '%d'";
        DBA dba = Helper.getDBA();
        try {
            ResultSet rs = dba.executeQuery(String.format(query, billId));

            while (rs.next()) {
                this.id = rs.getInt("billId");
                this.patientId = rs.getInt("patientId");
                this.dateCreated = rs.getTimestamp("dateCreated");
                this.datePaid = rs.getTimestamp("datePaid");
                this.consultationCost = rs.getInt("consultationCost");
            }
            rs.close();
            dba.closeConnections();

        } catch (SQLException sqlEx) {
            dba.closeConnections();
            Helper.logException(sqlEx);
        }
        return this;
    }