A Query Algebra for Fragmented XML Stream Data

  • Sujoe Bose
  • Leonidas Fegaras
  • David Levine
  • Vamsi Chaluvadi
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2921)


The increased usage of mobile devices coupled with an unprecedented demand for information has pushed the scalability problem of pull-based data service to the focus. A broadcast model of streaming data over a wireless medium has been proposed as a viable alternative for information dissemination. In the streaming broadcast model, servers broadcast data in an asynchronous and unacknowledged mode while clients process personalized and complex queries locally, relieving the load on the server. We address the query processing of streamed XML data, which is fragmented into manageable chunks for easier synchronization. Although there has been some work done in defining algebras that model XQueries on XML documents, no work has been done in defining query algebras for fragmented XML stream data. We define a model for processing fragmented XML stream data, using the concept of holes and fillers. This model offers the flexibility required by the server to disseminate data in manageable fragments, whenever they become available, and to send repetitions, replacements and removal of fragments. We then present a query algebra for XQuery that operates on this streamed XML data model. The XML fragments are operated upon in a continuous pipelined fashion without the need of materializing the transmitted document at the client site.


Query Processing Input Stream Continuous Query Path Expression XPath Query 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2004

Authors and Affiliations

  • Sujoe Bose
    • 1
  • Leonidas Fegaras
    • 1
  • David Levine
    • 1
  • Vamsi Chaluvadi
    • 1
  1. 1.Department of Computer Science and EngineeringUniversity of Texas at ArlingtonArlingtonUSA

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