Extended set operators for nested relations and complex objects

  • Eser Sükan
  • Z. Meral Özsoyoğlu
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 978)


Extended set operators defined originally for nested relations form a basis for the set operators for complex objects because the common approach based on the application of set operators to sets of oids (based on the equality of oids) alone is not sufficient as pointed out in the literature. Extended set operators operate directly on nested relations and produce nested relations. Hence, restructuring of the operands and the result are not needed. We consider the set operators for nested relations proposed in the literature and analyze them with respect to a property that we call information equivalence. We also show that some of these operators are not information equivalent. Then we define new extended set operators and show that they satisfy the information equivalence property. We also discuss different semantics (single value and complex object semantics) of nested relations and define the extended set operators accordingly.


Complex Objects Nested Relations Set Operators Object-Oriented Databases 


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Copyright information

© Springer-Verlag Berlin Heidelberg 1995

Authors and Affiliations

  • Eser Sükan
    • 1
  • Z. Meral Özsoyoğlu
    • 1
  1. 1.Computer Engineering and Science DepartmentCase Western Reserve UniversityCleveland

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