eCite Digital Repository

Performing grouping and aggregate functions in XML queries


Wu, H and Ling, TW and Xu, L and Bao, Z, Performing grouping and aggregate functions in XML queries, Proceedings of the 18th International Conference on World Wide Web, 20-24 April 2009, Madrid, Spain, pp. 1001-1010. ISBN 978-1-60558-487-4 (2009) [Refereed Conference Paper]

Copyright Statement

Copyright 2009 ACM

DOI: doi:10.1145/1526709.1526844


Since more and more business data are represented in XML format, there is a compelling need of supporting analytical operations in XML queries. Particularly, the latest version of XQuery proposed by W3C, XQuery 1.1, introduces a new construct to explicitly express grouping operation in FLWOR expression. Existing works in XML query processing mainly focus on physically matching query structure over XML document. Given the explicit grouping operation in a query, how to efficiently compute grouping and aggregate functions over XML document is not well studied yet. In this paper, we extend our previous XML query processing algorithm, VERT, to efficiently perform grouping and aggregate function in queries. The main technique of our approach is introducing relational tables to index values. Query pattern matching and aggregation computing are both conducted with table indices. We also propose two semantic optimizations to further improve the query performance. Finally we present experimental results to validate the efficiency of our approach, over other existing approaches.

Item Details

Item Type:Refereed Conference Paper
Keywords:aggregation, grouping, database, query processing, XML
Research Division:Information and Computing Sciences
Research Group:Data management and data science
Research Field:Data management and data science not elsewhere classified
Objective Division:Information and Communication Services
Objective Group:Information systems, technologies and services
Objective Field:Information systems, technologies and services not elsewhere classified
ID Code:92213
Year Published:2009
Deposited By:Information and Communication Technology
Deposited On:2014-06-10
Last Modified:2014-08-05

Repository Staff Only: item control page