问数据库创建了2个_id列，并且在拉出Base64字符串时出现问题

EN

public class MainActivity extends AppCompatActivity {


    private ListView mTopList, mDirectReportList;
    private ProgressBar mProgressBar;
    private ArrayList<Employee> mEmployees = new ArrayList<>();
    private BottomListViewAdapter mBottomListViewAdapter;
    EmployeeDBHandler dbHandler;
    SQLiteDatabase db;
    SimpleCursorAdapter simpleCursorAdapter;
    private int mStartingEmployeeID = startingEmployeeNumber;
    private String table = "employees";
    private static final String KEY_ID = "Employee_number";




    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        dbHandler = new EmployeeDBHandler(getApplicationContext());
        mProgressBar = (ProgressBar) findViewById(R.id.progressBar);
        mProgressBar.setVisibility(View.VISIBLE);






        getXMLData();




        //GUI for seeing android SQLite Database in Chrome Dev Tools
        Stetho.InitializerBuilder inBuilder = Stetho.newInitializerBuilder(this);
        inBuilder.enableWebKitInspector(Stetho.defaultInspectorModulesProvider(this));
        Stetho.Initializer in = inBuilder.build();
        Stetho.initialize(in);




    }


    public void getXMLData() {
        OkHttpClient client = getUnsafeOkHttpClient();
        Request request = new Request.Builder()
                .url(getString(R.string.API_FULL_URL))
                .build();
        client.newCall(request).enqueue(new Callback() {
            @Override
            public void onFailure(Call call, IOException e) {
                e.printStackTrace();
            }


            @Override
            public void onResponse(Call call, final Response response) throws IOException {
                final String responseData = response.body().string();
                final InputStream stream = new ByteArrayInputStream(responseData.getBytes());
                final XMLPullParserHandler parserHandler = new XMLPullParserHandler();
                final ArrayList<Employee> employees = (ArrayList<Employee>) parserHandler.parse(stream);


                for (Employee e : employees) {
                     dbHandler.addEmployee(e);
                }


                runOnUiThread(new Runnable() {
                    @Override
                    public void run() {
                        mProgressBar.setVisibility(View.GONE);
                        displayTopList();
                        displayBottomList();
                    }
                });
            }
        });
    }


    public void displayTopList() {
        Employee singleEmployee = dbHandler.getEmployee(mStartingEmployeeID);
        Log.i("The first name is: ", singleEmployee.getFirst_name());
    }


    public void displayBottomList() {
        SQLiteDatabase db = dbHandler.getWritableDatabase();
        Cursor mBottomListCursor = db.rawQuery("SELECT * FROM employees", null);


        ListView mBottomListView = (ListView) findViewById(R.id.mDirectReportList);
        BottomListViewAdapter bottomAdapter = new BottomListViewAdapter(this, mBottomListCursor);
        mBottomListView.setAdapter(bottomAdapter);
    }
}

public class EmployeeDBHandler extends SQLiteOpenHelper {
    private static final int DATABASE_VERSION = 1;
    private static final String DATABASE_NAME = "OneTeam";
    private static final String TABLE_EMPLOYEE = "employees";


    //Employee table columns names
    private static final String KEY_ID = "Employee_number";
    private static final String KEY_FIRST_NAME = "First_name";
    private static final String KEY_LAST_NAME = "Last_name";
    private static final String KEY_PHONE_NUMBER_MOBILE = "Phone_mobile";
    private static final String KEY_PHONE_NUMBER_OFFICE = "Phone_office";
    private static final String KEY_PAYROLL_TITLE = "Payroll_title";
    private static final String KEY_HAS_DIRECT_REPORTS = "Has_direct_reports";
    private static final String KEY_EMAIL = "Email";
    private static final String KEY_COST_CENTER = "Cost_center_id";
    private static final String KEY_THUMBNAIL_IMAGE = "ThumbnailData";
    private final static String DB_CLIENTS_ID = "_id";




    public EmployeeDBHandler(Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);


    }


    @Override
    public void onCreate(SQLiteDatabase db) {
        String CREATE_EMPLOYEE_TABLE = "CREATE TABLE IF NOT EXISTS " + TABLE_EMPLOYEE + "("
                + DB_CLIENTS_ID + " INTEGER PRIMARY KEY,"
                + KEY_ID + " TEXT,"
                + KEY_FIRST_NAME + " TEXT,"
                + KEY_LAST_NAME + " TEXT,"
                + KEY_PHONE_NUMBER_MOBILE + " TEXT,"
                + KEY_PHONE_NUMBER_OFFICE + " TEXT,"
                + KEY_PAYROLL_TITLE + " TEXT,"
                + KEY_HAS_DIRECT_REPORTS + " TEXT,"
                + KEY_EMAIL + " TEXT,"
                + KEY_THUMBNAIL_IMAGE + " TEXT,"
                + KEY_COST_CENTER + " TEXT,"
                + "UNIQUE(" + KEY_ID + ")"
                + ")";
        db.execSQL(CREATE_EMPLOYEE_TABLE);
    }


    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        //drop old table if existence
        db.execSQL("DROP TABLE IF EXISTS " + TABLE_EMPLOYEE);


        //Create table again
        onCreate(db);
    }


    //Add new employee
    public boolean addEmployee(Employee employee) {
        SQLiteDatabase database = this.getWritableDatabase();
        ContentValues values = new ContentValues();
        values.put(KEY_ID, employee.getEmployee_number());
        values.put(KEY_FIRST_NAME, employee.getFirst_name());
        values.put(KEY_LAST_NAME, employee.getLast_name());
        values.put(KEY_PHONE_NUMBER_MOBILE, employee.getPhone_mobile());
        values.put(KEY_PHONE_NUMBER_OFFICE, employee.getPhone_office());
        values.put(KEY_HAS_DIRECT_REPORTS, employee.getHas_direct_reports());
        values.put(KEY_EMAIL, employee.getEmail());
        values.put(KEY_COST_CENTER, employee.getCost_center_id());
        values.put(KEY_PAYROLL_TITLE, employee.getPayroll_title());
        values.put(KEY_THUMBNAIL_IMAGE, employee.getThumbnailData());




        //Inserting Row
        database.replace(TABLE_EMPLOYEE, null, values);
        database.close();
        return true;
    }


    //Get single employee
    public Employee getEmployee(int employeeNumber) {
        SQLiteDatabase database = this.getReadableDatabase();
        Employee employee = null;


        Cursor cursor = database.query(TABLE_EMPLOYEE, new String[]{
                        KEY_ID, KEY_FIRST_NAME, KEY_LAST_NAME, KEY_PHONE_NUMBER_OFFICE, KEY_PHONE_NUMBER_MOBILE,
                        KEY_HAS_DIRECT_REPORTS, KEY_EMAIL, KEY_COST_CENTER, KEY_PAYROLL_TITLE, KEY_THUMBNAIL_IMAGE}, KEY_ID + "=?",
                new String[]{String.valueOf(employeeNumber)}, null, null, null, null);
        if (cursor != null) {
            if (cursor.moveToFirst()) {
                employee = new Employee(cursor.getString(0),
                        cursor.getString(1), cursor.getString(2), cursor.getString(3), cursor.getString(4),
                        cursor.getString(5), cursor.getString(6), cursor.getString(7), cursor.getString(8),
                        cursor.getString(9), cursor.getString(10), cursor.getString(11), cursor.getString(12),
                        cursor.getString(12), cursor.getString(14), cursor.getString(15), cursor.getString(16),
                        cursor.getString(17), cursor.getString(18), cursor.getString(19), cursor.getString(20),
                        cursor.getString(21), cursor.getString(22), cursor.getString(23), cursor.getString(24),
                        cursor.getString(24), cursor.getString(25), cursor.getString(26));
            }
        }
        cursor.close();
        database.close();
        return employee;


    }


    //Get All Employees
    public ArrayList<Employee> getAllEmployees() {
        ArrayList<Employee> employeeList = new ArrayList<>();
        //Select all query
        String selectQuery = "SELECT * FROM " + TABLE_EMPLOYEE;


        SQLiteDatabase database = this.getWritableDatabase();
        Cursor cursor = database.rawQuery(selectQuery, null);


        //looping through all rows and adding to list
        if (cursor.moveToFirst()) {
            do {
                Employee employee = new Employee();
                employee.setEmployee_number(cursor.getString(cursor.getColumnIndex(KEY_ID)));
                employee.setFirst_name(cursor.getString(cursor.getColumnIndex(KEY_FIRST_NAME)));
                employee.setLast_name(cursor.getString(cursor.getColumnIndex(KEY_LAST_NAME)));
                employee.setPhone_office(cursor.getString(cursor.getColumnIndex(KEY_PHONE_NUMBER_MOBILE)));
                employee.setPhone_mobile(cursor.getString(cursor.getColumnIndex(KEY_PHONE_NUMBER_OFFICE)));
                employee.setHas_direct_reports(cursor.getString(cursor.getColumnIndex(KEY_HAS_DIRECT_REPORTS)));
                employee.setEmail(cursor.getString(cursor.getColumnIndex(KEY_EMAIL)));
                employee.setCost_center_id(cursor.getString(cursor.getColumnIndex(KEY_COST_CENTER)));
                employee.setPayroll_title(cursor.getString(cursor.getColumnIndex(KEY_PAYROLL_TITLE)));
                employee.setThumbnailData(cursor.getString(cursor.getColumnIndex(KEY_THUMBNAIL_IMAGE)));
            } while (cursor.moveToNext());
        }


        //return employees list
        return employeeList;
    }


    //Get Employee Count
    public int getEmployeeCount() {
        String countQuery = "SELECT * FROM " + TABLE_EMPLOYEE;
        SQLiteDatabase database = this.getReadableDatabase();
        Cursor cursor = database.rawQuery(countQuery, null);
        cursor.close();


        return cursor.getCount();
    }


    //Updating single employee
    public int updateEmployee(Employee employee) {
        SQLiteDatabase database = this.getWritableDatabase();


        ContentValues values = new ContentValues();
        values.put(KEY_FIRST_NAME, employee.getFirst_name());
        values.put(KEY_LAST_NAME, employee.getLast_name());
        values.put(KEY_PHONE_NUMBER_MOBILE, employee.getPhone_mobile());
        values.put(KEY_PHONE_NUMBER_OFFICE, employee.getPhone_office());
        values.put(KEY_HAS_DIRECT_REPORTS, employee.getHas_direct_reports());
        values.put(KEY_EMAIL, employee.getEmail());
        values.put(KEY_COST_CENTER, employee.getCost_center_id());
        values.put(KEY_PAYROLL_TITLE, employee.getPayroll_title());
        values.put(KEY_THUMBNAIL_IMAGE, employee.getThumbnailData());


        return database.update(TABLE_EMPLOYEE, values, KEY_ID + " = ?",
                new String[]{String.valueOf(employee.getEmployee_number())});
    }


    //Delete single employee
    public void deleteEmployee(Employee employee) {
        SQLiteDatabase database = this.getWritableDatabase();
        database.delete(TABLE_EMPLOYEE, KEY_ID + " = ?",
                new String[]{String.valueOf(employee.getEmployee_number())});
        database.close();
    }


    //delete row
    public void delete(int id) {
        SQLiteDatabase db = this.getWritableDatabase();
        if (db == null) {
            return;
        }
        db.delete(TABLE_EMPLOYEE, "Employee+number = ?", new String[]{String.valueOf(id)});
        db.close();
    }
}