Fixpoint semantics and optimization of recursive Datalog programs with aggregates
نویسندگان
چکیده
منابع مشابه
Fixpoint semantics and optimization of recursive Datalog programs with aggregates
A very desirable Datalog extension investigated by many researchers in the last thirty years consists in allowing the use of the basic SQL aggregates min, max, count and sum in recursive rules. In this paper, we propose a simple comprehensive solution that extends the declarative least-fixpoint semantics of Horn Clauses, along with the optimization techniques used in the bottom-up implementatio...
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The addition of aggregates has been one of the most relevant enhancements to the language of answer set programming (ASP). They strengthen the modeling power of ASP, in terms of concise problem representations. While many important problems can be encoded using nonrecursive aggregates, some relevant examples lend themselves for the use of recursive aggregates. Previous semantic definitions typi...
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ژورنال
عنوان ژورنال: Theory and Practice of Logic Programming
سال: 2017
ISSN: 1471-0684,1475-3081
DOI: 10.1017/s1471068417000436