Complexity of existential positive first-order logic
نویسندگان
چکیده
منابع مشابه
Complexity of Existential Positive First-Order Logic
Let Γ be a (not necessarily finite) structure with a finite relational signature. We prove that deciding whether a given existential positive sentence holds in Γ is in LOGSPACE or complete for the class CSP(Γ )NP under deterministic polynomial-time many-one reductions. Here, CSP(Γ )NP is the class of problems that can be reduced to the constraint satisfaction problem of Γ under non-deterministi...
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ژورنال
عنوان ژورنال: Journal of Logic and Computation
سال: 2011
ISSN: 0955-792X,1465-363X
DOI: 10.1093/logcom/exr043