关键词: 频率向量, 压缩, 离散化, 查询处理, 倒排索引

Abstract: In full-text retrieval systems, keyword-based indexes is always an important technique for efficient information retrieval. Existing bitmaps can’t support queries based on the quantum of keywords and inverted files need a large amount of storage space. A compression method and a storage structure for a kind of index named frequency vectors is presented in this paper. Theoretical analysis gives a upper bound of compression ratio. Query processing method based on the compressed index is also discussed. Experimental results indicate that our compressed index can guarantee to obtain complete query results and high efficency.

Key words: frequency vector, compression, discretization, query processing, inverted index