数据库已创建但未记录任何记录插入

Question

我在设备上运行应用程序。以下是我创建的数据库助手类。

public class DatabaseHandler extends SQLiteOpenHelper {

    // All Static variables
    // Database Version
    private static final int DATABASE_VERSION = 1;

    // Database Name
    @SuppressLint("SdCardPath")
    private static final String DATABASE_NAME = "/mnt/sdcard/destinationManager.db";

    // Contacts table name
    private static final String TABLE_DESTINATIONS = "Destination";

    // Contacts Table Columns names
    private static final String KEY_ID = "id";
    private static final String KEY_ADDRESS = "adress";
    private static final String KEY_CITY = "city";
    private static final String KEY_COUNTRY = "country";
    private static final String KEY_CONTACT = "contact";

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

    // Creating Tables
    @Override
    public void onCreate(SQLiteDatabase db) {
        String CREATE_CONTACTS_TABLE = "CREATE TABLE " + TABLE_DESTINATIONS
                + "(" + KEY_ID + " INTEGER PRIMARY KEY," + KEY_ADDRESS
                + " TEXT," + KEY_CITY + " TEXT," + KEY_COUNTRY + "TEXT,"
                + KEY_CONTACT + "TEXT)";
        db.execSQL(CREATE_CONTACTS_TABLE);
    }

    // Upgrading database
    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        // Drop older table if existed
        db.execSQL("DROP TABLE IF EXISTS " + TABLE_DESTINATIONS);

        // Create tables again
        onCreate(db);
    }

    /**
     * All CRUD(Create, Read, Update, Delete) Operations
     */

    // Adding new contact
    public void addDestination(Destination destination) {
        SQLiteDatabase db = this.getWritableDatabase();

        ContentValues values = new ContentValues();
        values.put(KEY_ADDRESS, destination.getAddress());
        values.put(KEY_CITY, destination.getCity());
        values.put(KEY_COUNTRY, destination.getCountry());
        values.put(KEY_CONTACT, destination.getContact());

        // Inserting Row
        db.insert(TABLE_DESTINATIONS, null, values);
        db.close(); // Closing database connection
    }

    // Getting single contact
    Destination getDestination(int id) {
        SQLiteDatabase db = this.getReadableDatabase();

        Cursor cursor = db.query(TABLE_DESTINATIONS, new String[] { KEY_ID,
                KEY_ADDRESS, KEY_CITY, KEY_COUNTRY, KEY_CONTACT }, KEY_ID
                + "=?", new String[] { String.valueOf(id) }, null, null, null,
                null);
        if (cursor != null)
            cursor.moveToFirst();

        Destination destination = new Destination();
        destination.setid(Integer.parseInt(cursor.getString(0)));
        destination.setAddress(cursor.getString(1));
        destination.setCity(cursor.getString(2));
        destination.setCountry(cursor.getString(3));
        destination.setContact(cursor.getString(4));

        return destination;
    }

    // Getting All Contacts
    public ArrayList<Destination> getAllDestinations() {
        ArrayList<Destination> contactList = new ArrayList<Destination>();
        // Select All Query
        String selectQuery = "SELECT  * FROM " + TABLE_DESTINATIONS;

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

        // looping through all rows and adding to list
        if (cursor.moveToFirst()) {
            do {
                Destination destination = new Destination();
                destination.setid(Integer.parseInt(cursor.getString(0)));
                destination.setAddress(cursor.getString(1));
                destination.setCity(cursor.getString(2));
                destination.setCountry(cursor.getString(3));
                destination.setContact(cursor.getString(4));

                // Adding contact to list
                contactList.add(destination);
            } while (cursor.moveToNext());
        }

        // return contact list
        return contactList;
    }

    // Updating single contact
    public int updateContact(Destination destination) {
        SQLiteDatabase db = this.getWritableDatabase();

        ContentValues values = new ContentValues();
        values.put(KEY_ADDRESS, destination.getAddress());
        values.put(KEY_CITY, destination.getCity());
        values.put(KEY_COUNTRY, destination.getCountry());
        values.put(KEY_CONTACT, destination.getContact());

        // updating row
        return db.update(TABLE_DESTINATIONS, values, KEY_ID + " = ?",
                new String[] { String.valueOf(destination.getid()) });
    }

    // Deleting single contact
    public void deleteDestination(Destination destination) {
        SQLiteDatabase db = this.getWritableDatabase();
        db.delete(TABLE_DESTINATIONS, KEY_ID + " = ?",
                new String[] { String.valueOf(destination.getid()) });
        db.close();
    }

    // Getting contacts Count
    public int getDestinationCount() {
        Cursor cursor = null;
        int count = 0;
        SQLiteDatabase db = null;
        try {
            String countQuery = "SELECT  * FROM " + TABLE_DESTINATIONS;
            db = this.getWritableDatabase();
            cursor = db.rawQuery(countQuery, null);
            synchronized (db) {
                count = cursor.getCount();
            }
        } catch (Exception ex) {
            ex.printStackTrace();
        } finally {
            if (db != null && db.isOpen()) {
                cursor.close();
                db.close();
            }
        }
        // return count
        return count;
    }
}

数据库正在创建，但我无法插入记录，但不会出现错误。在插入记录之后，我正在读取数据库并计算记录但是得到了0.

Destination destination = new Destination();
            destination.setAddress(address.getText().toString());
            destination.setCity(city.getText().toString());
            destination.setCountry(country.getText().toString());
            destination.setContact(MyApplication.GetData().getContacts());
            DatabaseHandler db = new DatabaseHandler(
                    DestinationDetailActivity.this);
            db.addDestination(destination);
            int count = db.getDestinationCount();  

Answer 1

KEY_COUNTRY + "TEXT,"
  + KEY_CONTACT + "TEXT)";

您在列名和类型之间缺少空格。添加空格。卸载您的应用，以删除包含countryTEXT列名称的旧数据库，并再次执行onCreate()。