Set-term unification in a logic database language

  • Seung Jin Lim
  • Yiu-Kai Ng
Session 2B: Database
Part of the Lecture Notes in Computer Science book series (LNCS, volume 959)


Deterministic, parallel set-term unification algorithms for higher-order logic-based database languages, of which set terms have the commutative and idempotent properties, are lacking. As a result, an efficient, deterministic inference mechanism that can be used to determine answers to queries of these database languages is non-existent. To overcome these shortcomings, we propose a set-term unification approach for LDL/NR, a higher-order logic database language. Our approach not only computes all generalized ground unifiers of two given set terms in LDL/NR without duplicates, but also takes advantage of existing multiple processors for (potentially) computing all these unifiers in parallel.


Logic Program Leaf Node Atomic Type Logic Database Nest Relation 
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 1995

Authors and Affiliations

  • Seung Jin Lim
    • 1
  • Yiu-Kai Ng
    • 1
  1. 1.Computer Science DepartmentBrigham Young UniversityProvoUSA

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