Method and apparatus for generating index as well as search method and search apparatus

Abstract

The present invention provides a method and apparatus for generating index as well as a search method and a search apparatus. Index entry comprises at least a search item identifier corresponding to a search item, one or a plurality of index items generated from one or plural pieces of search information, and an accumulator for the search information. The accumulator is generated by accumulating the search information, or accumulating ciphertext of information containing the search information, or accumulating data mapped from information containing the search information. At the time of searching, the index items and the accumulator are provided to a searcher. The searcher extracts search information from the index items and checks whether the extracted search information is complete by using the accumulator. In one embodiment, the accumulator is incorporated in an encrypted inverted index.

Dependencies are inferred from the claim text.