Variations on a Theme: A Bibliography on Approaches to Theorem Proving Inspired From Satchmo

This articles is a structured bibliography on theorem provers, approaches to theorem proving, and theorem proving applications inspired from Satchmo, the model generation theorem prover developed in the mid 80es of the 20th century at ECRC, the European Computer- Industry Research Centre. Note that the bibliography given in this article is not exhaustive

Proving Finite Satisfiability of Deductive Databases

It is shown how certain refutation methods can be extended into semi-decision procedures that are complete for both unsatisfiability and finite satisfiability. The proposed extension is justified by a new characterization of finite satisfiability. This research was motivated by a database design problem: Deduction rules and integrity constraints in definite databases have to be finitely satisfiabl

Reftections on sorne fundamental issues of rule-based incremental update propagation

This paper addresses two fundamental aspects of update propagation in deductive databases: 1. How to incrementally compute the sets of updates induced by a deductive rule from the changes of the data sets on which the rule depends? and 2. How to express such incremental definitions by meaos of deductive rules defining induced updates? Both problems have already been addressed by many authors in various contexts. The motivation for coming up with yet another such paper comes from the impression that sorne of the very basic assumptions and justifications of the approaches proposed in literature have not been understood well enough. In this paper we therefore investigate the basic algebraic laws of incremental change computation as well as their direct encoding in form of deductive rules from a new perspective. In addition we address the problems arising when the entire process of update propagation is driven by a (semi-)naive fixpoint procedure applied to the rules encoding the incremental definitions of induced updates

Checking Consistency of Database Constraints

This paper addresses the problem of consistency of a set of integrity constraints itself, independent from any state. It is pointed out that database constraints have not only to be consistent, but in addition to be finitely satisfiable. This stronger property reflects that the constraints have to admit a finite set of (stored as well as derivable) facts. As opposed to consistency, being undecidable, finite satisfiability is semidecidable. For efficiency purposes we investigate methods that check both finite satisfiability as well as unsatisfiability . Two different methods are proposed which extend two alternative approaches to refutation

Sur la Validité des Schémas de Bases de Données

Les mises a jour (Tun schema de base de donnees peuvent porter sur ses trois Constituante, ( l ) les declarations de structures, (2) les regies de coherence (et de deduction) et (3) les transactions. Ces Constituante doivent verifier certaines proprietes, definissant les Schemas valides. Un Systeme de gestion de Schemas doit pouvoir verifier la validite des sche"mas (independamment de toute extension de la base) et detecter les modifications des Schemas violant les conditions de validite. Dans cet article nous decrivons tout d'abord Papproche que nous avons suivi pour realiser un Systeme de gestion des declarations de structures, premier composant disponible d'un Systeme de gestion de Schemas en cours de developpement. Cette approche fait de la validite de declarations de structures un probleme semblable a la verification des regies de coherence dans une base de donnees. Nous montrons ensuite que la validite des regies (de coherence et de deduction) correspond a une propriete logique plus forte que la consistence, la satisfaisabilite finie. Dans certains cas, cette propriete peut elre detected par des methodes de refutation de preuve automatique de theoremes. Considerant la resolution, sur laquelle s'appuient les procedures de refutation les plus performantes, nous caracterisons les additions necessaires pour etendre une procedure de refutation en une methode complete pour la satisfaisabilite finie. Une telle extension de la resolution est decrite

Update propagation in chimera, an active DOOD language

Propagating updates is an important task to be performed within many database services such as integrity checking, maintenance of materialized views, and condition monitoring. This paper is concerned with the propagation of updates in an active DOOD language. The approach proposed is to make use of Chimera triggers for computing induced updates. It will be shown how a subset of Chimera's deductive rules can be compiled to update propagation triggers. In its expressiveness the rule set considered corresponds to that of Datalog with sets and negation. Using triggers for implementing update propgation has the advantage that no special component has to be implemented as a trigger mechanism has. to exist anyway. In this paper we will not propose new techniques for computing induced updates but will transfer the techniques - well-known for the relational model - to the object-oriented case