Answering Queries Using Views in Description Logics

Diego Calvanese, Giuseppe De Giacomo, and Maurizio Lenzerini

Proc. of the 12th Int. Workshop on Description Logics (DL 1999). Volume 22 of CEUR Workshop Proceedings, 1999.

Answering queries using views amounts to computing the answer to a query having information only on the extension of a set of views. This problem is relevant in several fields, such as information integration, data warehousing, query optimization, etc. In this paper we address the problem of query answering using views for nonrecursive datalog queries embedded in a Description Logics (equipped with n-ary relations) knowledge base. We present the following results. Query answering using views is decidable in all cases. Specifically, if the set of all objects in the knowledge base coincides with the set of objects stored in the views (closed domain assumption), the problem is coNP complete, whereas if the knowledge base may contain additional objects (open domain assumption) it is solvable in double exponential time.

   title = "Answering Queries Using Views in Description Logics",
   year = "1999",
   author = "Diego Calvanese and De Giacomo, Giuseppe and Maurizio
   booktitle = "Proc. of the 12th Int. Workshop on Description Logics
(DL 1999)",
   pages = "9--13",
   volume = "22",
   series = "CEUR Workshop Proceedings,",
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