Introduction to Datalog

This means that any program written in a logic programming language, e.g. Datalog or Prolog, is nothing more than a set of sentences in logical form, expressing facts and rules about a given domain. This allows logic programming to boast some nice features that other paradigms lack, namely:

The innermost circle encapsulates relational algebra—something which you might be familiar with if you have SQL-experience—and shows Datalog as an immediate extension. All logic programs—that is, our collection of logic constraints—consist of a finite set of facts and rules, and Datalog programs are no exception.

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