On Simplification of Database Integrity Constraints

摘要: Without proper simplification techniques, database integrity checking can be prohibitively time consuming. Several methods have been developed for producing simplified incremental checks each update but none until now of sufficient quality and generality providing a true practical impact, the present paper is an attempt to fill this gap. On theoretical side, general characterization introduced problem constraints natural definition given what it means procedure ideal. We prove that ideality strictly related query containment; in fact, ideal pro-cedure only exist languages which containment decidable. However, simplifications do not qualify as may also relevant purposes. concrete approach based on transformation operators apply written rich DATALOG-like language with negation. The resulting produces, at design-time, parametric transaction patterns, then instantiated checked consistency run-time. These tests take place before execution update, so consistency-preserving updates are eventually database. extension more expressive application framework other contexts, such data integration concurrent systems, discussed. Our experiments show obtained our method give rise much better performance than previous further improvements achieved by executing update.