Resolving structural conflicts in the integration of Entity-Relationship schemas

  • Mong Li Lee
  • Tok Wang Ling
Federated Systems Design
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1021)


Schema integration is essential to define a global schema that describes all the data in existing databases participating in a distributed or federated database management system. This paper describes a different approach to integrate two Entity-Relationship (ER) schemas. We focus on the resolution of structural conflicts, that is, when related real world concepts are modelled using different constructs in different schemas. Unlike previous works, our approach only needs to resolve the structural conflict between an entity type in one schema and an attribute in another schema and the other structural conflicts are automatically resolved. We have an algorithm to transform an attribute in one schema into an equivalent entity type in another schema without any loss of semantics or functional dependencies which previous approaches have not considered.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1995

Authors and Affiliations

  • Mong Li Lee
    • 1
  • Tok Wang Ling
    • 1
  1. 1.Department of Information Systems & Computer ScienceNational University of SingaporeSingapore

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