如何从RecyclerView适配器托架访问数据库？

public class MyAdapter extends RecyclerView.Adapter<MyAdapter.ViewHolder> {
    private SQLiteDatabase mDatabase;

    public MyAdapter(Context context) {
        MyDatabaseHelper dbHelper = new MyDatabaseHelper(context);
        mDatabase = dbHelper.getWritableDatabase();
    }

    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        // 创建ViewHolder并返回
    }

    @Override
    public void onBindViewHolder(ViewHolder holder, int position) {
        // 绑定数据到ViewHolder
    }

    @Override
    public int getItemCount() {
        // 返回数据条目数量
    }

    public class ViewHolder extends RecyclerView.ViewHolder {
        // ViewHolder的定义
    }
}

public class MyDatabaseHelper extends SQLiteOpenHelper {
    private static final String DATABASE_NAME = "my_database";
    private static final int DATABASE_VERSION = 1;

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

    @Override
    public void onCreate(SQLiteDatabase db) {
        // 创建数据库表
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        // 更新数据库表
    }
}