Report Number: CS-TN-93-3
Institution: Stanford University, Department of Computer Science
Title: Correct View Update Translations via Containment
Author: Tomasic, Anthony
Date: December 1993
Abstract: One approach to the view update problem for deductive databases proves properties of translations - that is, a language specifies the meaning of an update to the intensional database (IDB) in terms of updates to the extensional database (EDB). We argue that the view update problem should be viewed as a question of the expressive power of the translation language and the computational cost of demonstrating properties of a translation. We use an active rule based database language as a means of specifying translations of updates on the IDB into updates on the EDB. This paper uses the containment of one datalog program (or conjunctive query) by another to demonstrate that a translation is semantically correct. We show that the complexity of correctness is lower for insertion than deletion. Finally, we discuss extension to the translation language.