ABSTRACT
Variables are the distinguishing new feature of XPath 2.0 which permits to select n-tuples of nodes in trees. It is known that the Core of XPath 2.0 captures n-ary first-order (FO) queries modulo linear time transformations. In this paper, we distinguish a fragment of Core XPath 2.0 that remains FO-complete with respect ton-ary queries while enjoying polynomial-time query answering.
- N. Alechina, S. Demri, and M. de Rijke. A modal perspective on path constraints. Journal of Logic and Computation, 13(6):939--956, 2003.Google Scholar
Cross Ref
- Marcelo Arenas, Pablo Barcelo, and Leonid Libkin. Combining temporal logics for querying XML documents. In International Conference on Database Theory, 2007. Google Scholar
Digital Library
- Guillaume Bagan. MSO queries on tree decomposable structures are computable with linear delay. In CSL, 2006. Google Scholar
Digital Library
- Pablo Barcelo and Leonid Libkin. Temporal logics over unranked trees. In LICS, pages 31--40. 2005. Google Scholar
Digital Library
- Michael Benedikt and Christoph Koch. XPath leashed. 2006. submitted.Google Scholar
- Patrick Blackburn and Jerry Seligman. Hybrid languages. Journal of Logic, Language and Information, 4(3):251--272, 1995.Google Scholar
Cross Ref
- D. Coppersmith and S. Winograd. Matrix multiplication via arithmetic progressions. ACM conference on Theory of computing, 1987. Google Scholar
Digital Library
- Bruno Courcelle. Linear delay enumeration and monadic second-order logic. 2006. submitted.Google Scholar
- Arnaud Durand and Etienne Grandjean. The Complexity of Acyclic Conjunctive Queries Revisited. 2004.Google Scholar
- Arnaud Durand and Etienne Grandjean. First-order queries on structures of bounded degree are computable with constant delay. ACM Transactions on Computational Logics, 2006. Google Scholar
Digital Library
- H. Ebbinghaus and J. Flum. Finite Model Theory. Springer Verlag, Berlin, 1999.Google Scholar
- M. Franceschet and E. Zimuel. Modal logic and navigational xpath: an experimental comparison. In Proceedings of Workshop Methods for Modalities, pages 156--172, 2005.Google Scholar
- Georg Gottlob, Christoph Koch, and Reinhard Pichler. Efficient algorithms for processing XPath queries. ACM Transactions on Database Systems, 30(2):444--491, 2005. Google Scholar
Digital Library
- Leonid Libkin. Logics over unranked trees: an overview. Logical Methods in Computer Science, 32):1--31, 2006.Google Scholar
- Maarten Marx. Conditional XPath. ACM Transactions on Database Systems, 30(4):929--959, 2005. Google Scholar
Digital Library
- Maarten Marx. First order paths in ordered trees. In International Conference on Database Theory, pages 114--128, 2005. Google Scholar
Digital Library
- F. Moller and A. Rabinovich. Counting on CTL: on the expressive power of monadic path logic. Information and Computation, 184(1):147--159, 2003. Google Scholar
Digital Library
- Frank Neven and Thomas Schwentick. Query automata over finite trees. TCS, 275(1-2):633--674, 2002. Google Scholar
Digital Library
- Thomas Schwentick. On diving in trees. In MFCS, pages 660--669, 2000. Google Scholar
Digital Library
- S. Shelah. The monadic theory of order. Annals of Mathematics, 102:379--419, 1975.Google Scholar
Cross Ref
- L. J. Stockmeyer. The Complexity of Decision Problems in Automata Theory. PhD thesis, Department of Electrical Engineering, MIT, 1974.Google Scholar
- Balder ten Cate and Maarten Marx. Axiomatizing the logical core of XPath 2.0. In ICDT, 2007. Google Scholar
Digital Library
- Wolfgang Thomas. Logical aspects in the study of tree languages. In 9th International Colloquium on Trees in Algebra and Programming, pages 31--50, 1984. Google Scholar
Digital Library
- Mihalis Yannakakis. Algorithms for acyclic database schemes. In Proceeding of VLDB, pages 82--94, 1981.Google Scholar
Index Terms
Polynomial time fragments of XPath with variables
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