Reformulation of XML Queries and Constraints

  • Alin Deutsch
  • Val Tannen
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2572)


We state and solve the query reformulation problem for XML publishing in a general setting that allows mixed (XML and relational) storage for the proprietary data and exploits redundancies (materialized views, indexes and caches) to enhance performance. The correspondence between published and proprietary schemas is specified by views in both directions, and the same algorithm performs rewriting-with-views, composition-with-views, or the combined effect of both, unifying the Global-As-View and Local-As-View approaches to data integration. We prove a completeness theorem which guarantees that under certain conditions, our algorithm will find a minimal reformulation if one exists. Moreover, we identify conditions when this algorithm achieves optimal complexity bounds. We solve the reformulation problem for constraints by exploiting a reduction to the problem of query reformulation.


Integrity Constraint Conjunctive Query Storage Schema Schema Correspondence XPath Expression 
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 2003

Authors and Affiliations

  • Alin Deutsch
    • 1
  • Val Tannen
    • 2
  1. 1.UC San DiegoSan Diego
  2. 2.University of PennsylvaniaPennsylvania

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