Abstract
As a query language for navigating XML trees and selecting a set of element nodes, XPath is ubiquitous in XML applications. One important issue of XPath queries is checking containment. In particular, we investigate a frequently used fragment of XPath that consists of node tests, the child axis (/), the descendant axis (//), branches ([]) and label wildcards (*). For special classes of pattern trees, the homomorphism algorithm returns false negatives. In order to address this problem, we propose two containment techniques, conditioned homomorphism and hidden conditioned homomorphism, and then present sound algorithms to check containment. The analytical result is given with an experiment.
Supported by the National Natural Science Foundation of China under Grant No. 60573094, Tsinghua Basic Research Foundation under Grant No. JCqn2005022 and Zhejiang Natural Science Foundation under Grant No. Y105230.
Preview
Unable to display preview. Download preview PDF.
Similar content being viewed by others
References
Amer-Yahia, S., Cho, S., Lakshmanan, L.V.S., Srivastava, D.: Minimi-zation of tree pattern queries. In: Proc of the 2001 ACM SIGMOD Conf. on Management of Data (2001)
Amer-Yahia, S., Cho, S., Laksshmanan, L.V.S., Srivastava, D.: Tree pattern query minimization. The VLDB Journal 11(4), 315–331 (2002)
Benedikt, M., Fan, W., Kuper, G.M.: Structural properties of XPath fragments. In: Calvanese, D., Lenzerini, M., Motwani, R. (eds.) ICDT 2003. LNCS, vol. 2572, Springer, Heidelberg (2002)
Boag, S., Chamberlin, D., Fernández, M.F., Florescu, D., Robie, J., Siméon, J.: XQuery 1.0: An XML Query Language, http://www.w3.org/TR/xquery.W3CWorkingdraft
Buneman, P., Davidson, S., Fan, W., Hara, C., Tan, W.: Reasoning about keys for xml (2000)
Calvanese, D., DeGiacomo, G., Vadi, M.: Decidable containment of recursive queries. In: Calvanese, D., Lenzerini, M., Motwani, R. (eds.) ICDT 2003. LNCS, vol. 2572, pp. 330–345. Springer, Heidelberg (2002)
Chandra, A., Merlin, P.: Optimal implementation of conjunctive queries in relational data bases. In: Proceedings of 9th ACM Symposium on Theory of Computing, pp. 77–90 (1977)
Clark, J.: XSL Transformations (XSLT), http://www.w3.org/TR/xslt.W3CWorkingdraft
Clark, J., DeRose, S.: XML Path Language (XPath) Version 1.0. W3C Working draft, http://www.w3.org/TR/xpath
DeRose, S., Maler, E., Orchard, D.: XML Linking Language (XLink) Version 1.0. W3C Working draft, http://www.w3.org/TR/xpath
DeRose, S., Jr., R.D., Grosso, P., Maler, E., Marsh, J., Walsh, N.: XML Pointer Language (XPointer). W3C Working draft, http://www.w3.org/TR/xptr
Miklau, G., Suciu, D.: Containment and equivalence for a fragment of XPath. Journal of the ACM 51(1), 2–45 (2004)
Milo, T., Suciu, D.: Index structures for path expressions. In: Beeri, C., Bruneman, P. (eds.) ICDT 1999. LNCS, vol. 1540, pp. 277–295. Springer, Heidelberg (1998)
Neven, F.: Automata Theory for XML researchers. SIGMOD Record 31(3), 39–46 (2002)
Neven, F.,, T.: XPath containment in the presence of disjunction, DTDs, and variables. In: Proc. 9th Int. Conf. on Database Theory (ICDT), Siena, pp. 315–329 (2003)
Schwentick, T.: XPath query containment. ACM SIGMOD Database priciples Column (2004)
Shmueli, O.: Equivalence of datalog queries is undecidable. The Journal of Logic Programming 15(3), 231–242 (1993)
Wood, P.T.: Containment for XPath fragments under DTD constraints. In: Calvanese, D., Lenzerini, M., Motwani, R. (eds.) ICDT 2003. LNCS, vol. 2572, pp. 300–314. Springer, Heidelberg (2002)
Wood, P.T.: Minimizing simple xpath expressions. In: Fourth International Workshop on the Web and Databases (WebDB 2001) (2001)
Wood, P.T.: On the equivalence of xml patterns. In: International Conference on Deductive and Object-Oriented Databases (DOOD), pp. 1152–1166 (2000)
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2006 Springer-Verlag Berlin Heidelberg
About this paper
Cite this paper
Liao, Y., Feng, J., Zhang, Y., Zhou, L. (2006). Hidden Conditioned Homomorphism for XPath Fragment Containment. In: Li Lee, M., Tan, KL., Wuwongse, V. (eds) Database Systems for Advanced Applications. DASFAA 2006. Lecture Notes in Computer Science, vol 3882. Springer, Berlin, Heidelberg. https://doi.org/10.1007/11733836_32
Download citation
DOI: https://doi.org/10.1007/11733836_32
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-540-33337-1
Online ISBN: 978-3-540-33338-8
eBook Packages: Computer ScienceComputer Science (R0)