它们还可以存储结构化类型的列或索引数据。

They can also store structured type columns or index data.

youdao

一个目录型网站需要一个名称的字顺列表来查找，但该列表不是一个结构化的、主题化的索引（如前所述）。

A directory-type site might require an alphabetical list of names to look up, but this would not be a structured, topical index (as explained above).

youdao

不管使用什么技术，索引大量非结构化数据是一件很艰难的任务。

Indexing large amounts of unstructured data is a difficult task regardless of the technologies involved.

youdao