Guarded-Based Disjunctive Tuple-Generating Dependencies

A Guarded-Based Disjunctive Tuple-Generating Dependencies

Rule-based languages lie at the core of several areas of central importance to databases and artificial intelligence, such as data exchange, deductive databases, and knowledge representation and reasoning, to name a few. An algorithmic task that involves rules and is crucial for the above applications is query answering. In this work, we perform an in-depth complexity analysis of query answerin...

Explorer Guarded - Based Disjunctive Tuple - Generating Dependencies

Reasoning with Disjunctive Constrained Tuple-Generating Dependencies

Towards Efficient Reasoning Under Guarded-Based Disjunctive Existential Rules

The complete picture of the complexity of answering (unions of) conjunctive queries under the main guarded-based classes of disjunctive existential rules has been recently settled. It has been shown that the problem is very hard, namely 2ExpTime-complete, even for fixed sets of rules expressed in lightweight formalisms. This gives rise to the question whether its complexity can be reduced by re...

On the Undecidability of the Equivalence of Second-Order Tuple Generating Dependencies

Second-Order tuple generating dependencies (SO tgds) were introduced by Fagin et al. to capture the composition of simple schema mappings. Testing the equivalence of SO tgds would be important for applications like model management and mapping optimization. However, we prove the undecidability of the logical equivalence of SO tgds. Moreover, under weak additional assumptions, we also show the u...