Heuristic Horizontal XML Fragmentation
نویسندگان
چکیده
A challenging question is how XML can be used to support distributed databases. This leads to the problem of how to obtain a suitable, cost-efficient distribution design for XML documents. In this paper we sketch a heuristic approach to minimise query costs for the case of horizontal fragmentation. The approach is based on a cost model that takes the complex structure of queries on XML documents into account. We show that the minimisation of transportation costs is decisive, and that this can be achieved locally by either accepting or rejecting a horizontal fragmentation with a simple predicate that arises from one of the most frequent queries.
منابع مشابه
Distribution Design for XML documents
The web is often seen as the world's largest database and XML is regarded to provide its data model. As XML data is naturally distributed across the web it should be considered as a distributed database and subject to distribution design. The main tasks of distribution design are fragmenting the underlying database schema and allocating the fragments to different sites. The aim of fragmentation...
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