A SchemaGuide for Accelerating the View Adaptation Process

Materialization of XML views significantly improves query performance in the often slow execution times for XPath expressions. Existing efforts focus on providing approaches of how to reuse materialized view for answering XPath queries and, the problem of synchronizing materialized data in response to the changes taking place at data source level. In this paper, we study a closely related problem, the view adaptation problem, which maintains the materialized data incrementally after view definitions have been redefined/changed (view redefinition). Our research focuses on an efficient process for view adaptation upon the fragment-based view representation by segmenting materialized data into fragments and developing algorithms to update only those materialized fragments that have affected by the view definition changes. This serves to minimize the effect of view adaptation and provide a more efficient process for stored views. Additionally, we study the containment problem at fragment level under the constraints expressed in a so-name SchemaGuide. We have implemented our view adaptation system and we present in this paper the performance analysis.