Safe Stratiied Datalog with Integer Order Does Not Have Syntax
نویسندگان
چکیده
Stratiied Datalog with integer (gap)-order (or Datalog :;<z) is considered. A Datalog :;<z-program is said to be safe ii its bottom-up processing terminates on all valid inputs. We prove that safe Datalog :;<z-programs do not have eeective syntax in the sense that there is no recursively enumerable set S of safe Datalog :;<z-programs such that every safe Datalog :;<z-program is equivalent to a program in S.
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