Abstract
In this paper, we introduce two efficient search methods that heuristically find proper replications close to the optimal value. These searched replications can notably reduce the overall query cost in mapping XML into relations. The necessity of such an automatic tool arises from the complexity of XML, i.e., the fact that it is difficult to search the optimal replication set to enhance query performance because of mass complex XML data and queries. Moreover, it was observed that the search problem requires exponential time of the number of given queries. Another important problem in implementing them is that exact query cost can not be measured within reasonable time. That is, actually executing an XML query over actual relational schema costs much time whenever a replication is evaluated in the algorithms, and effective estimation technique is needed. To overcome the obstacle, we considered the histogram-based estimation in commercial RDBMS. It is very simple and can support exact estimation. In addition, it can resolve the trait of highly skewed structure in XML very well. Finally, the effect of two search methods and the estimation are analyzed through some experiments.
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References
Goldberg, D.E.: Genetic algorithms in search, optimization, and machine learning. Addison-Wesley Publishing Company, Reading (1989)
Kanne, C.C., Moerkotte, G.: Efficient storage of XML data. In: Proceedings of International Conference on DATA ENGINEERING, California, USA, p. 198 (2000)
Graefe, G., McKenna, W.J.: The volcano optimizer generator: Extensibility and efficient search. In: Proceedings of International Conference on DATA ENGINEERING, pp. 209–218 (1993)
Piatetsky-Shapiro, G., Connell, C.: Accurate estimation of the number of tuples satisfying a condition. In: Proceedings of the ACM SIGMOD International Conference on Management of Data, pp. 256–276 (1984)
Freire, J., Haritsa, J.R., Ramanath, M., Roy, P., Siméon, J.: StatiX: Making XML count. In: Proceedings of the ACM SIGMOD International Conference on Management of Data, pp. 181–191 (2002)
Kim, J., Park, S.: Performance Enhancement through structural redundancy in mapping XML into relations. In: Proceedings of the Eighth database systems for advanced applications, pp. 345–353. IEEE Computer Society Press, Los Alamitos (2003)
McHugh, J., Widom, J.: Query optimization for XML. In: Proceedings of VLDB, pp. 315–326 (1999)
Shanmugasundaram, J., Shekita, E., Barr, R., Carey, M., Lindsay, B., Pirahesh, H., Reinwald, B.: Efficiently publishing relational data as XML documents. In: Proceedings of VLDB, Cairo, Egypt, pp. 65–76 (2000)
Polyzotis, N., Garofalakis, M.: Statistical synopses for graph-structured XML databases. In: Proceedings of the ACM SIGMOD International Conference on Management of Data, pp. 358–369 (2002)
Selinger, P., Astrahan, M., Chamberlin, D., Lorie, R., Price, T.: Access path selection in a relational database management system. In: Proceedings of the ACM SIGMOD International Conference on Management of Data, pp. 23–34 (1979)
Lipton, R.J., Naughton, J.F., Schneider, D.A.: Practical selectivity estimation through adaptive sampling. In: Proceedings of the ACM SIGMOD International Conference on Management of Data, pp. 1–11 (1990)
Poosala, V., Ioannidis, Y., Haas, P., Shekita, E.: Improved histograms for selectivity estimation of range predicates. In: Proceedings of the ACM SIGMOD International Conference on Management of Data, pp. 294–305 (1996)
Sun, W., Ling, Y., Rish, N., Deng, Y.: An instant and accurate size estimation method for joins and selections in a retrieval-intensive environment. In: Proceedings of the ACM SIGMOD International Conference on Management of Data, pp. 79–88 (1993)
Ioannidis, Y., Christodoulakis, S.: Optimal histograms for limiting worst-case error propagation in the size of join results. ACM TODS 18(4), 709–748 (1993)
Wu, Y., Patel, J.M., Jagadish, H.V.: Estimating answer sizes for XML queries. In: Jensen, C.S., Jeffery, K., Pokorný, J., Šaltenis, S., Bertino, E., Böhm, K., Jarke, M. (eds.) EDBT 2002. LNCS, vol. 2287, pp. 590–608. Springer, Heidelberg (2002)
Kim, J.-H., Park, S.: Flexible modification of relational schema by x2RMap in storing XML into relations. In: Shafazand, H., Tjoa, A.M. (eds.) EurAsia-ICT 2002. LNCS, vol. 2510, p. 330. Springer, Heidelberg (2002)
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Kim, J., Park, S. (2004). Searching Proper Replications in Mapping XML into Relations. In: Lee, Y., Li, J., Whang, KY., Lee, D. (eds) Database Systems for Advanced Applications. DASFAA 2004. Lecture Notes in Computer Science, vol 2973. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-540-24571-1_24
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DOI: https://doi.org/10.1007/978-3-540-24571-1_24
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