public void insertIntoStaffTable(int user_id, Staff staff) {

    StringBuffer strQuery = new StringBuffer(INSERT_STAFF_QUERY);
    strQuery.append(user_id);
    strQuery.append("', '");
    strQuery.append(staff.getStaff_ssn());
    strQuery.append("', '");
    strQuery.append(staff.getWork_desc());
    strQuery.append("', '");
    strQuery.append(staff.getPosition());
    strQuery.append("', '");
    strQuery.append(utility.convertStringToDate(staff.getHire_date()));
    strQuery.append("')");
    System.out.println("Insert Staff query : " + strQuery.toString());

    try {
      DBOperation.executeQuery(strQuery.toString());
    } catch (Exception e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
    }
  }