Historical and computational aspects of paraconsistency in view of the logic foundation of databases

We expose paraconsistent logic with regard to its potential to contribute to the foundations of databases. We do so from a historical perspective, starting at the ancient inception and arriving at the contemporary use of logic as a computational device., We show that an understanding of the logic foundations of databases in-terms of paraconsistency is adequate. It avoids absurd connotations of the ex contradictione quodlibet principle, which in fact never applies in databases. We interpret datalog, its origins and some of its extensions by negation and abduction, in terms of paraconsistency. We propose a procedural definition of paraconsistency and show that many well-known query answering procedures comply with it.