A Guide to Designing Top-k Indexes

Top-k search, which reports the k elements of the highest importance from all the elements in an underlying dataset that satisfy a certain predicate, has attracted significant attention from the database community. The search efficiency crucially depends on the quality of an index structure that can be utilized to filter the underlying data by both the user-specified predicate and the ranking of importance. This article introduces the reader to a list of techniques for designing such indexes with strong performance guarantees. Several promising directions for future work are also discussed.