We show that, although conjunctive queries over OWL 2 QL ontologies are reducible to database queries, no algorithm can construct such a reduction in polynomial time without changi...
Stanislav Kikot, Roman Kontchakov, Michael Zakhary...
An important means of allowing non-expert end-users to pose ad hoc queries — whether over single databases or data integration systems — is through keyword search. Given a set...
Query result caching is an important mechanism for search engine efficiency. In this study, we first review several query features that are used to determine the contents of a sta...
A number of existing information retrieval systems propose the notion of query context to combine the knowledge of query and user into retrieval to reveal the most exact descripti...
Keke Cai, Chun Chen, Jiajun Bu, Peng Huang, Zhimin...
We present a continuously adaptive, continuous query (CACQ) implementation based on the eddy query processing framework. We show that our design provides significant performance b...
Samuel Madden, Mehul A. Shah, Joseph M. Hellerstei...