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Static Analysis and Query Answering for Incomplete Data Trees with Constraints

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In Search of Elegance in the Theory and Practice of Computation

Part of the book series: Lecture Notes in Computer Science ((LNTCS,volume 8000))

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Data trees serve as an abstraction of XML documents: in such trees, every node comes with a label from a finite alphabet, as well as a data value from an infinite set. Incomplete data trees model XML documents with incomplete information; they may include both structural incompleteness and incompleteness of data. Here we study two basic problems for incomplete data trees under typical constraints such as keys and foreign keys. The first problem is consistency of specifications of incomplete data trees. We show that many of recently established results on consistency of constraints and schema descriptions can be transferred to the consistency of incomplete tree specifications without any increase in complexity. After that we examine query answering over incomplete data trees under constraints, and show that tractable bounds can be recovered under key constraints, but are lost under foreign keys.

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Gheerbrant, A., Libkin, L., Reutter, J. (2013). Static Analysis and Query Answering for Incomplete Data Trees with Constraints. In: Tannen, V., Wong, L., Libkin, L., Fan, W., Tan, WC., Fourman, M. (eds) In Search of Elegance in the Theory and Practice of Computation. Lecture Notes in Computer Science, vol 8000. Springer, Berlin, Heidelberg.

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  • Print ISBN: 978-3-642-41659-0

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