On Graph Refutation for Relational Inclusions
Paulo A. S. Veloso, Sheila R. M. Veloso · Electronic Proceedings in Theoretical Computer Science · 2012
We introduce a graphical refutation calculus for relational inclusions: it reduces establishing a relational inclusion to establishing that a graph constructed from it has empty extension. This sound and complete calculus is conceptually simpler and easier to use than the usual ones.