Evaluating Algorithms for TOPOLOGICAL ROLLUP in XML-OLAP

摘要

The essence of XML data is the interchange of electronic data between data sources on the web. Therefore, XML is playing an important role in data storage and transmission. Whereas wide spectrum of data is represented in XML format, complex analysis on XML data becomes progressively important. To respond to the demand, we have proposed a system for XML data analysis adopting the features of OLAP system which we call XML-OLAP. Recently, we migrate our research to structure-based grouping for our XML-OLAP system that is TOPOLOGICAL ROLLUP. Based on the well-known algorithms of Structural Join, we proposed some algorithms for TOPOLOGICAL ROLLUP, namely Top-Down, Bottom-UP, and Single Scan by Preorder/Postorder number. In this paper, we will describe the algorithms, evaluation on the proposed algorithms, and show their performance with synthesized data varying by some features which enable us to make proper assessment.