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View-based query answering in description logics: Semantics and complexity

Calvanese D; De Giacomo G; Lenzerini M; Rosati R (2012)
View-based query answering is the problem of answering a query based only on the precomputed answers to a set of views. While this problem has been widely investigated in databases, it is largely unexplored in the context ...
Data complexity of query answering in description logics

Calvanese D; De Giacomo G; Lembo D; Lenzerini M; Rosati R (2013)
In this paper we study data complexity of answering conjunctive queries over Description Logic (DL) knowledge bases constituted by an ABox and a TBox. In particular, we are interested in characterizing the FOL-rewritability ...
Query Processing under GLAV Mappings for Relational and Graph Databases

Calvanese D; De Giacomo G; Lenzerini M; Vardi M (2012)
Schema mappings establish a correspondence between data stored in two databases, called source and target respectively. Query processing under schema mappings has been investigated extensively in the two cases where each ...