14:00, Room N107 (Parc Club)
Evaluating conjunctive queries over a relational database is a central problem of database theory. This problem is also closely related to constraint satisfaction problems in artificial intelligence. We discuss decomposition methods, that are an efficient ways to cope with the computational intractability of these problems. Then we discuss semantic interoperability problems in coalitions of autonomous sources, where we present the advantages of adopting a constraint optimization-based framework. We also discuss other related questions in Web data management, in particular entity matching in Web document collections and Twitter streams.