Transaction management in RDBMSs with XML support
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The wide use of XML as a description format for semistructured data resulted in the development of XML data management facilities for the existing relational database management systems (RDBMSs). The leading vendors of RDBMSs have included the support of the XML query and update languages in their systems. However, because of considerable differences between the relational and XML data models, transaction management methods in RDBMS are not quite appropriate for XML data. A series of our experiments with RDBMSs with XML support have revealed that, when accessing the same XML document for reading and updating, the transactions are executed sequentially, although they do not conflict. Thus, concurrency of XML transactions in RDBMSs is essentially limited. In the paper, a new method of the XML transaction management in RDBMSs is described. Our method is based on a two-level transaction model. The key component of this model is the new concurrency control protocol, called XDGL, especially tailored for synchronization of the XML transactions. The XDGL protocol is implemented on the top of the existing RDBMS transaction manager. A software prototype of the suggested method has been implemented for Microsoft SQL Server 2005. Our experiments have revealed considerable reduction of the XML transaction execution time when the number of parallel queries and updates is large.
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- 1.Yergeau, F., Bray, T., Paoli, J., Sperberg-McQueen, C.M., and Maler, E., Extensible Markup Language. W3C Recommendation. 4th February 2004. http://www.w3.org/TR/2004/REC-xml-20040204.
- 2.Boag, S., Chamberlin, D., Fernandez, M., Florescu, D., Robie, J., and Simeon, J., Xquery 1.0: An XML Query Language. W3C Working Draft. 11 February 2005. http://www.w3.org/TR/xquery/.
- 3.Schmidt, A., Waas, F., Kersten, M., Florescu, D., Manolescu, I., Carey, M., and Busse, R., The XML Benchmark Project, Technical Report INS-R0103, Amsterdam: CWI, 2001.Google Scholar
- 4.Gray, J. and Renter, A., Transaction Processing: Concepts and Techniques, San Francisco: Morgan Kaufmann, 1993.Google Scholar
- 6.Weikum, G. and Schek, H.J., Database Transaction Models for Advanced Applications, San Francisco: Morgan Kaufmann, 1992.Google Scholar
- 7.Pleshachkov, P., Chardin, P., and Kuznetsov, S., A DataGuide-Based Concurrency Control Protocol for Cooperation on XML Data, Lecture Notes in Computer Science (Proc. of the 9th East Eur. Conf. on Advances in Databases and Information Systems ADBIS-2005, Tallinn, 2005), Berlin: Springer, 2005, vol. 3631, pp. 268–282.Google Scholar
- 8.Goldman, R. and Widom, J., DataGuides: Enabling Query Formulation and Optimization in Semistructured DataBases, Proc. the 23d Int. Conf. on Very Large Databases (Athens, 1997), San Francisco: Morgan Kaufmann, 1997, pp. 436–445.Google Scholar
- 9.Tatarinov, I., Ives, Z., Halevy, A., and Weld, D., Updating XML, Proc. ACM SIGMOD 2001, Santa Barbara, 2001. http://www.cis.upenn.edu/:_zives/research/updatingXML.pdf.
- 10.Pleshachkov, P., Chardin, P., and Kuznetsov, S., XDGL: XPath-Based Concurrency Control Protocol for XML Data, Lecture Notes in Computer Science (Proc. of the 22nd British National Conference on Databases, Sunderland, 2005), Berlin: Springer, 2005, vol. 3567, p. 145.Google Scholar
- 12.Hunt, H.B. and Rosenkrantz, D.J., The Complexity of Testing Predicate Locks, Proc. the 1979 ACM SIGMOD 1979 Int. Conf. on Management of Data (Boston, 1979), New York: ACM, 1979, pp. 127–133.Google Scholar
- 13.Rosenkrantz, D.J. and Hunt, H.B., Processing Conjunctive Predicates and Queries, Proc. the Sixth Int. Conf. on Very Large Data Bases (Montreal, 1980), Los Altos: IEEE Comput. Soc., 1980, pp. 64–72.Google Scholar
- 14.Bernstein, P., Hadzilakos, V., and Goodman, N., Concurrency Control and Recovery in Database Systems, Reading: Addison-Wesley, 1987.Google Scholar
- 15.Haustein, M.P. and Harder, T., taDOM: A Tailored Synchronization Concept with Tunable Lock Granularity for the DOM API, Lecture Notes in Computer Science (Proc. the 7th East European Conf. on Advances in Databases and Information Systems, Dresden, 2003), Berlin: Springer, 2003, vol. 2798, pp. 88–102.Google Scholar
- 16.Helmer, S., Kanne, C.-C., and Moerkotte, G., Lock-Based Protocols for Cooperation on XML Documents, Proc. the 14th Int. Workshop on Database and Expert Systems Applications, Prague, 2003, pp. 230–234.Google Scholar
- 17.Dekeyser, S. and Hidders, J., Conflict Scheduling of Transactions on XML Documents, Proc. 15th Australian Database Conf. (Dunedin, 2004), Darlinghurst: Australian Comput. Soc., 2004, pp. 93–101.Google Scholar
- 18.Jea, K., Chen, S.Y., and Wang, S.H., Concurrency Control in XML Document DataBases: XPath Locking Protocol, Proc. the 9th Int. Conf. on Parallel and Distributed Systems (Taiwan, 2002), Washington: IEEE Comput.er Soc., 2002, pp. 551–556.Google Scholar
- 19.Grabs, T., Böhm, K., and Schek, H.-J., XMLTM: Efficient Transaction Management for XML Documents, Proc. the 11th int. Conf. on Information and Knowledge Management (McLean, 2002), New York: ACM, 1979, pp. 142–152.Google Scholar
- 20.Berglund, A., Boag, S., Chamberlin, D., Fernandez, M.F., Kay, M., Robie, J., and Simeon, J., XML Path Language (XPath) 2.0. W3C Working Draft. 11 February 2005 http://www.w3.org/TR/2005/WD-xpath20-20050211/.
- 21.Deutsch, A., Fernandez, M.F., and Suciu, D., Storing Semistructured Data with STORED, Proc. the ACM SIGMOD Int. Conf. on Management of Data (Philadelphia, 1999), New York: ACM, 1999, pp. 431–442.Google Scholar
- 22.Kay, M., XSL Transformations (XSLT) Version 2.0. W3C Working Draft. 11 February 2005. http://www.w3.org/TR/2005/WD-xslt20-20050211/.
- 23.Malhotra, A., Melton, J., and Walsh, N., XQuery 1.0 and XPath 2.0 Functions and Operators W3C Working Draft. 15 September 2005. http://www.w3.org/TR/2005/WD-xpath-functions-20050915/.
- 24.Rys, M., Norie, M.C., and Schek, H.J., Intra-Transaction Parallelism in the Mapping of an Object Model to a Relational Multi-Processor System, Proc. the 22th Int. Conf. on Very Large Databases (Bombay, 1996), San Francisco: Morgan Kaufmann, 1996, pp. 460–471.Google Scholar
- 25.Weikum, G. and Vossen, G., Transactional Information Systems, San Francisco: Morgan Kaufmann, 2002.Google Scholar