Adding structure to unstructured data

  • Peter Buneman
  • Susan Davidson
  • Mary Fernandez
  • Dan Suciu
Contributed Papers Session 7: Unstructured Data
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1186)

Abstract

We develop a new schema for unstructured data. Traditional schemas resemble the type systems of programming languages. For unstructured data, however, the underlying type may be much less constrained and hence an alternative way of expressing constraints on the data is needed. Here, we propose that both data and schema be represented as edge-labeled graphs. We develop notions of conformance between a graph database and a graph schema and show that there is a natural and efficiently computable ordering on graph schemas. We then examine certain subclasses of schemas and show that schemas are closed under query applications. Finally, we discuss how they may be used in query decomposition and optimization.

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Copyright information

© Springer-Verlag 1997

Authors and Affiliations

  • Peter Buneman
    • 1
  • Susan Davidson
    • 1
  • Mary Fernandez
    • 2
  • Dan Suciu
    • 2
  1. 1.University of PennsylvaniaUSA
  2. 2.AT&T Labs - ResearchUSA

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