B-tree structured data base using sparse array bit maps to store inverted lists

摘要

Variable length data (e.g., for hospital patients) is embedded in a B- tree type index structure of a relational data base. A logically related inverted B-tree index is used to access the original index. Access time, and storage space for the inverted lists, are decreased by data compression techniques and by encoding certain inverted list parameters in sparse array bit maps.