Scalable Distributed Query and Update Service Implementations for XML Document Elements
|Title||Scalable Distributed Query and Update Service Implementations for XML Document Elements|
|Author(s)||T. Grabs, K. Böhm, H.-J. Schek|
|Booktitle||Proceedings of the Eleventh International Workshop on Research Issues in Data Engineering: Document Management for Data Intensive Business and Scientific Applications Heidelberg, Germany|
AbstractMaterialization and indexing of XML views is an important issue, and a number of 'XML-to-database' mappings have been proposed. To build a scalable system for XML document storage where those views are up-to-date, we must provide efficient implementations of basic services for query processing and updates. As a first contribution we define such services, and show that they support many 'XML-to-database' mappings. As a second and main contribution, we describe implementations of such services in a database cluster. We evaluate two implementations, one based on a two-level logging and isolation mechanism and one using Windows 2000 COM+ transactions. The main results are as follows: the first approach scales linearly for updates, and query response times are interactive. For example, with high workloads of 100 concurrent clients and 8 cluster components, response times are 3 seconds on average. The alternative approach is weaker both regarding query response times (10 seconds on average for the above scenario) and scalability.