Moshe Y. Vardi
ABSTRACT
From the mid 1980s to the mid 1990s, with the active involvement of Paris C. Kanellakis, a major theme in database theory was the study of Datalog, the language of logic programs without function symbols. Unfortunately, most decision problems involving Datalog turned out to be undecidable. Furthermore, well-behaved fragments of Datalog turned out to be rather restrictive and unnatural. Surprisingly, a natural and quite general fragment of Datalog did emerge in the mid 1990s, in the context of semistructured data. This fragment is the class of regular queries, whose basic element is that of regular path queries. In this talk I describe the class of regular queries and its well-behavedness in the context of view-based query processing.
- D. Calvanese, G. De~Giacomo, M. Lenzerini, and M. Y. Vardi. Rewriting of regular expressions and regular path queries. In Proc. of the 18th ACM SIGACT SIGMOD SIGART Sym. on Principles of Database Systems (PODS'99), pages 194--204, 1999. Extended version appeared in J. of Computer and System Sciences, 64, 2002. Google Scholar
Digital Library
- D. Calvanese, G. De~Giacomo, M. Lenzerini, and M. Y. Vardi. Answering regular path queries using views. In Proc. of the 16th IEEE Int. Conf. on Data Engineering (ICDE~2000), pages 389--398, 2000. Google ScholarDigital Library
- D. Calvanese, G. De~Giacomo, M. Lenzerini, and M. Y. Vardi. Containment of conjunctive regular path queries with inverse. In Proc. of the 7th Int. Conf. on the Principles of Knowledge Representation and Reasoning (KR~2000), pages 176--185, 2000.Google Scholar
- D. Calvanese, G. De~Giacomo, M. Lenzerini, and M. Y. Vardi. Query processing using views for regular path queries with inverse. In Proc. of the 19th ACM SIGACT SIGMOD SIGART Sym. on Principles of Database Systems (PODS~2000), pages 58--66, 2000. Google ScholarDigital Library
- D. Calvanese, G. De~Giacomo, M. Lenzerini, and M. Y. Vardi. View-based query processing and constraint satisfaction. In Proc. of the 15th IEEE Sym. on Logic in Computer Science (LICS~2000), pages 361--371, 2000. Google ScholarDigital Library
- D. Calvanese, G. De~Giacomo, M. Lenzerini, and M. Y. Vardi. What is query rewriting? In Proc. of the 7th Int. Workshop on Knowledge Representation meets Databases (KRDB~2000), pages 17--27. CEUR Electronic Workshop Proceedings, http://ceur-ws.org/Vol-29/, 2000.Google ScholarCross Ref
- D. Calvanese, G. De~Giacomo, M. Lenzerini, and M. Y. Vardi. Lossless regular views. In Proc. of the 21st ACM SIGACT SIGMOD SIGART Sym. on Principles of Database Systems (PODS~2002), pages 247--258, 2002. Google ScholarDigital Library
- D. Calvanese, G. De~Giacomo, M. Lenzerini, and M. Y. Vardi. View-based query answering and query containment over semistructured data. In G. Ghelli and G. Grahne, editors, Revised Papers of the 8th International Workshop on Database Programming Languages (DBPL~2001), volume 2397 of Lecture Notes in Computer Science, pages 40--61. Springer, 2002. Google ScholarDigital Library
- D. Calvanese, G. De~Giacomo, M. Lenzerini, and M. Y. Vardi. View-based query containment. In Proc. of the 22st ACM SIGACT SIGMOD SIGART Sym. on Principles of Database Systems (PODS~2003), 2003. To appear. Google ScholarDigital Library
Index Terms
- A call to regularity
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