Organization and analysis of access facilities for set-valued objects based on signature files

摘要

Set is a fundametal data structure and plays important role in data modeling not only for traditional database aplications but for advanced ones. The main issue of this dissertation is indexing methods for set-valued objects. Set has several inherent comparison operators such as inclusion ([?]) and membership ([?]). Therefore, indexing methods for set-valued objects must support efficient retrieval of objects under such set retrieval conditions. In this dissertation, superimposed-coded signature files, popular methods in text retrieval area, are proposed as promising indexing methods for set-valued objects. Such signature files are called set-based signature files. In this dissertation, several issues of set-based signature foles, such as organization schemes, retrieval/update algorithms, and availability, are investigated. ･･･