IRMA-International.org: Creator of Knowledge
Information Resources Management Association
Advancing the Concepts & Practices of Information Resources Management in Modern Organizations

On the Query Evaluation in XML Databases

On the Query Evaluation in XML Databases
View Sample PDF
Author(s): Yangjun Chen (University of Winnipeg, Canada)
Copyright: 2009
Pages: 10
Source title: Handbook of Research on Innovations in Database Technologies and Applications: Current and Future Trends
Source Author(s)/Editor(s): Viviana E. Ferraggine (UNICEN, Argentina), Jorge Horacio Doorn (UNICEN, Argentina)and Laura C. Rivero (UNICEN, Argentina)
DOI: 10.4018/978-1-60566-242-8.ch070

Purchase

View On the Query Evaluation in XML Databases on the publisher's website for pricing and purchasing information.

Abstract

With the growing importance of XML in data exchange, much research has been done in providing flexible query mechanisms to extract data from XML documents. A core operation for XML query processing is to find all occurrences of a twig pattern Q (or small tree) in a document T. Prior work has typically decomposed Q into binary structural relationships, such as parent-child and ancestor-descendant relations, or root-to-leaf paths. The twig matching is achieved by: (a) matching the binary relationships or paths against XML databases, and (b) using the join algorithms to stitch together all the matching binary relationships or paths. In the worst case, the time for doing joins can be exponential (in the number of query nodes or decomposed paths). In this chapter, we discuss a new algorithm for this task with no path joins involved. The time and space complexities of the algorithm are bounded by O (|T|·Qleaf) and O (Tleaf·Qleaf), respectively, where Tleaf stands for the number of the leaf nodes in T and Qleaf for the number of the leaf nodes in Q. Our experiments show that our method is efficient in supporting twig pattern queries.

Related Content

Renjith V. Ravi, Mangesh M. Ghonge, P. Febina Beevi, Rafael Kunst. © 2022. 24 pages.
Manimaran A., Chandramohan Dhasarathan, Arulkumar N., Naveen Kumar N.. © 2022. 20 pages.
Ram Singh, Rohit Bansal, Sachin Chauhan. © 2022. 19 pages.
Subhodeep Mukherjee, Manish Mohan Baral, Venkataiah Chittipaka. © 2022. 17 pages.
Vladimir Nikolaevich Kustov, Ekaterina Sergeevna Selanteva. © 2022. 23 pages.
Krati Reja, Gaurav Choudhary, Shishir Kumar Shandilya, Durgesh M. Sharma, Ashish K. Sharma. © 2022. 18 pages.
Nwosu Anthony Ugochukwu, S. B. Goyal. © 2022. 23 pages.
Body Bottom