Types of acyclicity
نویسندگان
چکیده
منابع مشابه
On the Relationship of Joint Acyclicity and Super-Weak Acyclicity
Rules that allow existential quantifiers in the head (conclusion) have been studied extensively in knowledge representation, databases, and logic programming (in the related form of logic programs with function symbols). In general, it is not decidable if a set of such rules admits a finite model, but a number of sufficient conditions have been proposed to detect situations where this is the ca...
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ژورنال
عنوان ژورنال: Journal of Pure and Applied Algebra
سال: 1974
ISSN: 0022-4049
DOI: 10.1016/0022-4049(74)90009-7