Android 小项目之SQLite 使用法门

public void onCreate(SQLiteDatabase db) {

// TODO Auto-generated method stub

String sql="Create table "+TABLE_NAME+"("+FIELD_ID+" integer primary key autoincrement,"

+FIELD_TITLE+" text );";

db.execSQL(sql);

}

@Override

public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

// TODO Auto-generated method stub

String sql=" DROP TABLE IF EXISTS "+TABLE_NAME;

db.execSQL(sql);

onCreate(db);

}

public Cursor select()

{

SQLiteDatabase db=this.getReadableDatabase();

Cursor cursor=db.query(TABLE_NAME, null, null, null, null, null, " _id desc");

return cursor;

}

public long insert(String Title)

{

SQLiteDatabase db=this.getWritableDatabase();

ContentValues cv=new ContentValues();

cv.put(FIELD_TITLE, Title);

long row=db.insert(TABLE_NAME, null, cv);

return row;

}

public void delete(int id)

{

SQLiteDatabase db=this.getWritableDatabase();

String where=FIELD_ID+"=?";

String[] whereValue={Integer.toString(id)};

db.delete(TABLE_NAME, where, whereValue);

}

public void update(int id,String Title)

{

SQLiteDatabase db=this.getWritableDatabase();

String where=FIELD_ID+"=?";

String[] whereValue={Integer.toString(id)};

ContentValues cv=new ContentValues();

cv.put(FIELD_TITLE, Title);

db.update(TABLE_NAME, cv, where, whereValue);

}

}

创建和打开数据库

上篇通过构造函数来创建数据库，看一下构造函数的方法

android.database.sqlite.SQLiteOpenHelper.SQLiteOpenHelper(Context context, String name, CursorFactory factory, int version)