Experiencing Intuitionistic Logic Programming in SQL Puzzles

Abstract

This work presents some SQL puzzles making use of the application of intuitionistic logic programming (ILP) to implement an SQL system. ILP provides a way of declaring SQL Common Table Expressions as used to specify recursive queries and local view definitions. We present the concepts of ILP that will be used to translate SQL queries to Hypothetical Datalog, providing its syntax, an inference system and translation rules. Then, several novel SQL puzzles used during teaching standard SQL in a database subject are proposed, showing that when following the SQL standard the implemented system is more expressive than current DMBS's.