Teaching a Schema Translator to Produce O/R Views

  • Peter Mork
  • Philip A. Bernstein
  • Sergey Melnik
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4801)


This paper describes a rule-based algorithm to derive a relational schema from an extended entity-relationship model. Our work is based on an approach by Atzeni and Torlone in which the source EER model is imported into a universal metamodel, a series of transformations are performed to eliminate constructs not appearing in the relational metamodel, and the result is exported. Our algorithm includes novel features that are needed for practical object to relational mapping systems: First, it generates forward- and reverse-views that transform instances of the source model into instances of the target and back again. These views automate the object-to-relational (O/R) mapping. Second, it supports a flexible mapping of inheritance hierarchies to flat relations that subsumes and extends prior approaches. Third, it propagates incremental updates of the source model into incremental updates of the target. We prove the algorithm’s correctness and demonstrate its practicality in an implementation.


Source Model Target Model Target Schema Schema Translation Abstract Type 
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 2007

Authors and Affiliations

  • Peter Mork
    • 1
  • Philip A. Bernstein
    • 2
  • Sergey Melnik
    • 2
  1. 1.The MITRE CorporationUSA
  2. 2.Microsoft ResearchAustralia

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