backtracking is perilous in general; logic programming languages have really nice abilities for such but I don't know how to avoid pathological inefficiency.
Re-evaluation of a tabled predicate is avoided by memoizing the answers. This can realise huge performance enhancements as illustrated in section 7.1. It also comes with two downsides: the memoized answers are not automatically updated or invalidated if the world (set of predicates on which the answers depend) changes and the answer tables must be stored (in memory).
Known to the Prolog community since about the 1980's if I got my references right.
