在mvvm模式下，使用android room从数据库中提取数据时，逻辑应该放在哪里？

@Entity(tableName = "user_table")
public class User {
    @PrimaryKey(autoGenerate = true)
    private int id;
    private String name;
    private String email;

    // Getters and Setters
}

@Dao
public interface UserDao {
    @Query("SELECT * FROM user_table")
    LiveData<List<User>> getAllUsers();

    @Insert(onConflict = OnConflictStrategy.IGNORE)
    void insert(User user);
}

@Database(entities = {User.class}, version = 1, exportSchema = false)
public abstract class UserDatabase extends RoomDatabase {
    public abstract UserDao userDao();
}

public class UserViewModel extends ViewModel {
    private UserDao userDao;
    private LiveData<List<User>> allUsers;

    public UserViewModel(Application application) {
        UserDatabase database = Room.databaseBuilder(application, UserDatabase.class, "user_database").build();
        userDao = database.userDao();
        allUsers = userDao.getAllUsers();
    }

    public LiveData<List<User>> getAllUsers() {
        return allUsers;
    }

    public void insert(User user) {
        new InsertUserAsyncTask(userDao).execute(user);
    }

    private static class InsertUserAsyncTask extends AsyncTask<User, Void, Void> {
        private UserDao asyncTaskDao;

        InsertUserAsyncTask(UserDao dao) {
            asyncTaskDao = dao;
        }

        @Override
        protected Void doInBackground(final User... params) {
            asyncTaskDao.insert(params[0]);
            return null;
        }
    }
}

public class MainActivity extends AppCompatActivity {
    private UserViewModel userViewModel;

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

        userViewModel = new ViewModelProvider(this).get(UserViewModel.class);

        userViewModel.getAllUsers().observe(this, new Observer<List<User>>() {
            @Override
            public void onChanged(List<User> users) {
                // Update UI with the list of users
            }
        });
    }
}