如何保存一个预定义的db文件并在android中用SQLiteDatabase类打开它？

public class DBHelper extends SQLiteOpenHelper {
    private static final String DB_NAME = "your_db_file.db";
    private static final int DB_VERSION = 1;

    public DBHelper(Context context) {
        super(context, DB_NAME, null, DB_VERSION);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        // 如果需要创建表，可以在这里执行创建表的操作
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        // 如果需要升级数据库，可以在这里执行升级操作
    }
}

DBHelper dbHelper = new DBHelper(context);
SQLiteDatabase db = dbHelper.getReadableDatabase(); // 或者使用getWritableDatabase()

// 查询示例
Cursor cursor = db.query("table_name", null, null, null, null, null, null);
if (cursor != null) {
    while (cursor.moveToNext()) {
        // 处理查询结果
    }
    cursor.close();
}

// 插入示例
ContentValues values = new ContentValues();
values.put("column_name", "value");
long rowId = db.insert("table_name", null, values);

// 更新示例
ContentValues values = new ContentValues();
values.put("column_name", "new_value");
int rowsAffected = db.update("table_name", values, "column_name=?", new String[]{"value"});

// 删除示例
int rowsAffected = db.delete("table_name", "column_name=?", new String[]{"value"});