在android mvvm中我们在哪里改进了call & db CRUD？

@Entity(tableName = "user_table")
data class User(
    @PrimaryKey(autoGenerate = true)
    val id: Int,
    val name: String,
    val email: String
)

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

    @Insert(onConflict = OnConflictStrategy.IGNORE)
    suspend fun insert(user: User)

    @Update
    suspend fun update(user: User)

    @Delete
    suspend fun delete(user: User)
}

class UserRepository(private val userDao: UserDao) {
    val allUsers: LiveData<List<User>> = userDao.getAllUsers()

    suspend fun insert(user: User) {
        userDao.insert(user)
    }

    suspend fun update(user: User) {
        userDao.update(user)
    }

    suspend fun delete(user: User) {
        userDao.delete(user)
    }
}

class UserViewModel(private val repository: UserRepository) : ViewModel() {
    val allUsers: LiveData<List<User>> = repository.allUsers

    fun insert(user: User) = viewModelScope.launch {
        repository.insert(user)
    }

    fun update(user: User) = viewModelScope.launch {
        repository.update(user)
    }

    fun delete(user: User) = viewModelScope.launch {
        repository.delete(user)
    }
}