Conjunctive Query Containment in Description Logics with n-ary Relations.
Diego Calvanese, Giuseppe De Giacomo, Maurizio Lenzerini · 1997
Recent research points out that query containment is a central problem in several database and knowledge base applications, including data warehousing, data integration, query optimization, and (materialized) view maintenance. In this paper we present a decision procedure for containment of conjunctive queries defined over a database schema specified in a very expressive description logic, comprising n-ary relations and general inclusion axioms on both concepts and relations. 1 Introduction Query containment is the problem of checking whether for every data (or knowledge) base, the result of one query is always a subset of the result of another query. Many recent papers point out that query containment is a central problem in several database and knowledge base applications, including data warehousing, data integration, query optimization, (materialized) view maintenance, etc. (see for example [11, 1, 10]). The issue of developing algorithms for query containment has been addressed b...