Rank-aware query processsing and optimization

Efficient execution of ranking query is increasingly becoming a major challenge for database technology. DBMSs provide efficient update, indexing, concurrency and recovery. On the other hand, IR on text and multimedia requires techniques involving uncertainty and ranking for effective retrieval. The main goal of this paper is to give an in-depth look on supporting ranking queries as an increasingly interesting area of research. We cover the state-of-the-art techniques in research prototypes and industry-strength database engines for efficient handling of ranking and queries. We focus primarily on how to integrate ranking as a new query processing and optimization dimension, with the aim of supporting ranking queries as a basic and core functionality. The paper identifies several challenges that need to be addressed towards a true support for ranking and effective retrieval in database management systems.