ROL is a deductive object-oriented database system developed at the University of Regina. It supports important object-oriented features such as object identity, complex objects, classes, class hierarchies, multiple inheritance with overriding and blocking, and schema deenition. It also supports structured values such as functor objects and sets, providing powerful mechanisms for representing b...

A new temporal deductive database system supporting a non-standard model of time is introduced. It consists of Non-standard Temporal Datalog (nstl) and Non-standard Temporal Relational Algebra (nstra). The time line consists of non-standard reals that are of the form 〈r, z〉, where r ∈ R and z ∈ Z, using the natural order. Each real r determines a macro-instant, and each pair 〈r, z〉 defines a mi...

In this paper we describe a distributed environment for the evaluation of data intensive queries through deductive rules. The distributed database query answering system has been developed on the IBM SP (POWERParallel) available in Argonne National Laboratory. Beyond acting as a testbed, experiments with the system demonstrate that it ooers signiicantly improved performance over single processo...

We describe the design and implementation of the Glue-Nail deductive database system. Nail is a purely declarative query language; Glue is a procedural language used for non-query activities. The two languages combined are suucient to write a complete application. Nail and Glue code are both compiled into the target language IGlue. The Nail compiler uses variants of the magic sets algorithm and...

The traditional focus of knowledge engineering has been to acquire knowledge that can be used in deductive inference. Acquiring such knowledge invariably requires users to undergo extensive training. There are, however, aspects of the knowledge necessary for deductive inference that require much less training and sophistication. For example, capturing knowledge involving ground facts and concep...

We present in this paper both a novel theoretically well-founded framework for integrating the treatment of advanced update and rule enforcement problems in deductive databases and the architecture of a new deductive database management system based upon such a framework. Our results extend the query-processing and basic updating functionalities provided by current deductive database systems wi...

We demonstrate the use of a hyper-programming system in building persistent applications. This allows program representations to contain type-safe links to persistent objects embedded directly within the source code. The benefits include improved efficiency and potential for static program checking, reduced programming effort and the ability to display meaningful source-level representations fo...

Logic based knowledge processing systems such as PROLOG based expert systems have shown obvious drawbacks in performing conventional database tasks. Knowledge processing by deduction on a large set of given facts can be better performed by a deductive database system based on Horn logic and relational database theory. A concept is presented to extend an existing relational database system to ma...

Disjunctive Deductive Databases (DDDBs) | function-free disjunctive logic programs with negation in rule bodies allowed | have been recently recognized as a powerful tool for knowledge representation and commonsense reasoning. Much research has been spent on issues like semantics and complexity of DDDBs, but the important area of implementing DDDBs has been less addressed so far. However, a tho...