Negation and Aggregates in Recursive Rules: the LDL++ Approach

@inproceedings{Zaniolo1993NegationAA,
  title={Negation and Aggregates in Recursive Rules: the LDL++ Approach},
  author={Carlo Zaniolo and Natraj Arni and KayLiang Ong},
  booktitle={DOOD},
  year={1993}
}
The problem of allowing non-monotonic constructs, such as negation and aggregates, in recursive programs represents a difficult challenge faced by current research in deductive databases. In this paper, we present a solution that combines generality with efficiency, as demonstrated by its implementation in the new LDL++ system. A novel and general treatment of set aggregates, allowing for user-defined aggregates, is also presented. 
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