Cost-Based Vertical Fragmentation for XML

Abstract

The Extensible Markup Language (XML) has attracted much attention as a data model for data exchange, data integration and rich data representation. A challenging question is how to manage native XML data in distributed databases. This leads to the problem of how to obtain a suitable distribution design for XML documents. In this paper we present a design approach for vertical fragmentation to minimise total query costs. Our approach is based on a cost model that takes the complex structure of queries on XML data into account. We show that system performance can be improved after vertical fragmentation using our approach, which is based on user access patterns.

Prefix-Based Labeling Annotation for Effective Xml Fragmentation

“…In this scenario, horizontal fragmentation may reduce the transportation cost and processing time as the data is determined in a specific distributed note. Moreover, horizontal fragmentation can easily transport data between sites to improve system performance [8].…”

“…Vertical fragmentation is a kind of affinity-based fragmentation. As opposed to horizontal fragmentation, this type of fragmentation does not encourage transportation of data from node to node which will trade off flexibility to affinity [8].…”

An Overview of Fragmentation Design for Distributed XML Databases

“…Finally, the minimum total query cost will determine how the document should be fragmented [13,14] Sven et al proposed simplified cost model that work similar to previous method. The query processing cost model is based on the size estimation on the query results and query processing costs to determine the fragmentation of XML document [8].…”