Some Remarks on the Definability of Transitive Closure in First-order Logic and Datalog
نویسنده
چکیده
In the last WSML phone conference we had a brief discussion about the expressivity of First-order Logic and Datalog resp. the relation between the expressiveness of those two languages. In particular, there has been some confusion around the description of the transitive closure R of some binary relation R. In this short document, we want to clarify the situation and hope to remedy the confusion.
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