在android中将Sqlite数据转换为CSV文件

public class DbHelper extends SQLiteOpenHelper {
    private static final String DATABASE_NAME = "mydatabase.db";
    private static final int DATABASE_VERSION = 1;

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

    @Override
    public void onCreate(SQLiteDatabase db) {
        // 创建数据库表
        db.execSQL("CREATE TABLE IF NOT EXISTS mytable (id INTEGER PRIMARY KEY, name TEXT, age INTEGER)");
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        // 升级数据库表
        db.execSQL("DROP TABLE IF EXISTS mytable");
        onCreate(db);
    }

    public Cursor getData() {
        SQLiteDatabase db = getReadableDatabase();
        return db.rawQuery("SELECT * FROM mytable", null);
    }
}

public class MainActivity extends AppCompatActivity {
    private static final String CSV_FILE_PATH = Environment.getExternalStorageDirectory().getPath() + "/data.csv";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        // 创建数据库帮助类实例
        DbHelper dbHelper = new DbHelper(this);

        // 获取查询结果的Cursor对象
        Cursor cursor = dbHelper.getData();

        // 创建CSV文件
        try {
            FileWriter writer = new FileWriter(CSV_FILE_PATH);

            // 写入CSV文件的表头
            writer.append("id,name,age\n");

            // 遍历查询结果，将数据写入CSV文件
            while (cursor.moveToNext()) {
                int id = cursor.getInt(cursor.getColumnIndex("id"));
                String name = cursor.getString(cursor.getColumnIndex("name"));
                int age = cursor.getInt(cursor.getColumnIndex("age"));

                // 写入CSV文件的一行数据
                writer.append(id + "," + name + "," + age + "\n");
            }

            writer.flush();
            writer.close();

            Toast.makeText(this, "CSV文件已保存至：" + CSV_FILE_PATH, Toast.LENGTH_SHORT).show();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />