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在Android平臺(tái)上，集成了一個(gè)嵌入式關(guān)系型數(shù)據(jù)庫(kù)—SQLite。如果你想要開(kāi)發(fā) Android 應(yīng)用程序，一定需要在 Android 上存儲(chǔ)數(shù)據(jù)，使用SQLite 數(shù)據(jù)庫(kù)是一種非常好的選擇。

下面介紹的基本使用：

是一個(gè)抽象類(lèi)不能直接實(shí)例化，所以新建一個(gè)類(lèi)DBOpenHelper繼承自SQLiteOpenHelper ：

public class DBOpenHelper extends SQLiteOpenHelper {

	public DBOpenHelper(Context context) {

		super(context, "yhn.db", null, 1);

	}

	//數(shù)據(jù)庫(kù)第一次創(chuàng)建時(shí)候調(diào)用，

	public void onCreate(SQLiteDatabase db) {

		db.execSQL("create table user(uid integer primary key autoincrement, uname varchar(20), uaddress varchar(20))");

	}

	//數(shù)據(jù)庫(kù)文件版本號(hào)發(fā)生變化時(shí)調(diào)用

	public void onUpgrade(SQLiteDatabase arg0, int arg1, int arg2) {

	}

如果執(zhí)行上邊的代碼，則會(huì)創(chuàng)建一個(gè)數(shù)據(jù)庫(kù)文件xx.db

數(shù)據(jù)庫(kù)操作類(lèi)：

public class DBDao {

	DBOpenHelper dbOpenHelper;

	

	public DBDao(Context context){

		this.dbOpenHelper=new DBOpenHelper(context);

	}

	/**

	 * 添加一條數(shù)據(jù)

	 * @param user

	 */

	public void save(User user){

		SQLiteDatabase db=dbOpenHelper.getWritableDatabase();

		db.execSQL("insert into user(uname,uaddress) values(?,?)", new Object[]{user.getUname(),user.getUaddress()});

		db.close();

	}

	/**

	 * 刪除一條數(shù)據(jù)

	 * @param uid

	 */

	public void delete(Integer uid){

		SQLiteDatabase db=dbOpenHelper.getWritableDatabase();

		db.execSQL("delete from user where uid=?", new Object[]{uid});

		db.close();

	}

	/**

	 * 更新一條數(shù)據(jù)

	 * @param user

	 */

	public void update(User user){

		SQLiteDatabase db=dbOpenHelper.getWritableDatabase();

		db.execSQL("update user set uname=?,uaddress=? where uid=?", new Object[]{user.getUname(),user.getUaddress(),user.getUid()});

		db.close();

	}

	/**

	 * 查找一條數(shù)據(jù)

	 * @param uid

	 */

	public User find(Integer uid){

		SQLiteDatabase db=dbOpenHelper.getReadableDatabase();

		Cursor cursor =db.rawQuery("select * from user where uid=?", new String[]{uid.toString()});

		if(cursor.moveToFirst()){

			int uid2=cursor.getInt(cursor.getColumnIndex("uid"));

			String uname=cursor.getString(cursor.getColumnIndex("uname"));

			String uaddress=cursor.getString(cursor.getColumnIndex("uaddress"));

			User user=new User();

			user.setUid(uid2);

			user.setUname(uname);

			user.setUaddress(uaddress);

			return user;

		}

		cursor.close();

		return null;

	}

	/**

	 * 分頁(yè)查找數(shù)據(jù)

	 * @param offset 跳過(guò)多少條數(shù)據(jù)

	 * @param maxResult 每頁(yè)多少條數(shù)據(jù)

	 * @return 

	 */

	public List getScrollData(int offset, int maxResult){

		Listusers=new ArrayList();

		SQLiteDatabase db=dbOpenHelper.getReadableDatabase();

		Cursor cursor =db.rawQuery("select * from user order by uid asc limit ?,?", new String[]{String.valueOf(offset), String.valueOf(maxResult)});

		while(cursor.moveToNext()){

			int uid2=cursor.getInt(cursor.getColumnIndex("uid"));

			String uname=cursor.getString(cursor.getColumnIndex("uname"));

			String uaddress=cursor.getString(cursor.getColumnIndex("uaddress"));

			User user=new User();

			user.setUid(uid2);

			user.setUname(uname);

			user.setUaddress(uaddress);

			users.add(user);

		}

		return users;

	}

	/**

	 * 獲取數(shù)據(jù)總數(shù)

	 * @return

	 */

	public long getCount(){

		SQLiteDatabase db=dbOpenHelper.getReadableDatabase();

		Cursor cursor =db.rawQuery("select count(*) from user", null);

		cursor.moveToFirst();

		long reslut=cursor.getLong(0);

		return reslut;

	}

}

示例：向數(shù)據(jù)庫(kù)中添加一條數(shù)據(jù)

DBDao dbDao=new DBDao(this);

        User user=new User();

        user.setUname("qixiaohu");

        user.setUaddress("chengdu");

        dbDao.save(user);

PC上管理SQLite數(shù)據(jù)庫(kù)的方法：

上邊添加數(shù)據(jù)后可以看到數(shù)據(jù)添加成功：

該文章在 2013/2/25 14:33:24 編輯過(guò)