Prolog is a terrible "programming language" - and I would never try to use it as such. But it is (at least conceptually) an excellent query language. In that regard, it is much closer to SQL, as is its domain of reasonably applicable problems.
Clarification: I dont actually think prolog is terrible (I credit it as the most exciting language I have ever learned), I just mean its not intuitive to "program" with in the imperative sense of telling a computer what to do. What I mean by it is excellent as a query language is - given a set of data, it is great for drawing conclusions from that data (but not in the same way as a "traditional" query language like SQL).
Clarification: I dont actually think prolog is terrible (I credit it as the most exciting language I have ever learned), I just mean its not intuitive to "program" with in the imperative sense of telling a computer what to do. What I mean by it is excellent as a query language is - given a set of data, it is great for drawing conclusions from that data (but not in the same way as a "traditional" query language like SQL).