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Schema-based Scheduling of Event Processors and Buffer Minimization for Queries on Structured Data Streams

Christoph Koch·Stefanie Scherzinger·Nicole Schweikardt·Bernhard Stegmaier
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Abstract

We introduce an extension of the XQuery language, FluX, that supports event-based query processing and the conscious handling of main memory buffers. Purely event-based queries of this language can be executed on streaming XML data in a very direct way. We then develop an algorithm that allows to efficiently rewrite XQueries into the event-based FluX language. This algorithm uses order constraints from a DTD to schedule event handlers and to thus minimize the amount of buffering required for evaluating a query. We discuss the various technical aspects of query optimization and query evaluation within our framework. This is complemented with an experimental evaluation of our approach.

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Christoph Koch, Stefanie Scherzinger, Nicole Schweikardt, Bernhard Stegmaier. 2004-06-07. Schema-based Scheduling of Event Processors and Buffer Minimization for Queries on Structured Data Streams. https://arxiv.org/abs/cs/0406016

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