【预研】搜索引擎基础——inverted index(倒排索引)

基础知识思考整理

http://blog.csdn.net/aganlengzi/article/details/53130790

inverted index：In computer science, an inverted index (also referred to as postings file or inverted file) is an index data structure storing a mapping from content, such as words or numbers, to its locations in a database file, or in a document or a set of documents (named in contrast to a Forward Index, which maps from documents to content).[1]

倒排索引：应该是翻译的锅了… … 感觉叫反向索引可能更好一点。

常规的索引是文档到关键词的映射：文档——>关键词

倒排索引是关键词到文档的映射：关键词——>文档

之所以这么干是想通过关键词方便快捷地找到相关的文档，是搜索引擎的重要基础技术。

关于inverted index的具体原理，这个里面讲得比较清楚。

[1] https://en.wikipedia.org/wiki/Inverted_index

[2] http://blog.csdn.net/malefactor/article/details/7256305

[2] https://www.zhihu.com/question/23202010/answer/23928943