| Autor: |
Horrocks, Ian, Tessaris, Sergio, Sattler, Ulrike, Tobies, Stephan |
| Jazyk: |
angličtina |
| Rok vydání: |
1999 |
| Předmět: |
|
| Druh dokumentu: |
Report |
| Popis: |
Query containment under constraints is the problem of determining whether the result of one query is contained in the result of another query for every database satisfying a given set of constraints. This problem is of particular importance in information integration and warehousing where, in addition to the constraints derived from the source schemas and the global schema, inter-schema constraints can be used to specify relationships between objects in different schemas. A theoretical framework for tackling this problem using the DLR logic has been established, and in this paper we show how the framework can be extended to a practical decision procedure. The proposed technique is to extend DLR with an Abox (a set of assertions about named individuals and tuples), and to transform query subsumption problems into DLR Abox satisfiability problems. We then show how such problems can be decided, via a reification transformation, using a highly optimised reasoner for the SHIQ description logic. |
| Databáze: |
Networked Digital Library of Theses & Dissertations |
| Externí odkaz: |
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