Commentary by cpressey on Relational Programming works
Relational Methods in Computer Science
Overview of relational programming
A report on a research program to develop a (point-free) relational programming language.
The investigation proceeds at the language design level only - implementation issues are hardly considered. A major concern of the language design is to be able to express operations on non-linear data (e.g. trees) (in contrast to e.g. APL's ability to manipulate linear data, e.g. matrices).
[Introduction to relational programming][] is an earlier report on the same research program, but the syntax has evolved between the two points. In particular, given that all functions are relations, function application is a subset of relation application, but the side on which the function is considered to be, has been swapped since the earlier paper.
Introduction to relational programming
[Overview of relational programming][] is probably a better paper, but this does contain some worked examples of relational programs (for payroll, etc.)