Avoid duplication of data elements.

避免出现重复的数据元素。

youdao

It is like a view; there is no duplication of the underlying data.

它看上去像一个视图，并且底层数据不存在重复。

youdao

It is like a view; there is no duplication of the underlying data.

它看上去像一个视图，并且底层数据不存在重复。

youdao