Object-Based Semantic Real-Time Concurrency Control with Bounded Imprecision

This paper describes a concurrency control technique for real-time object-oriented databases that supports logical consistency and temporal consistency, as well as bounded imprecision that results from their trade-o s. The concurrency control technique uses a semantic locking mechanismwithin each object and user-de ned conditional compatibility over the methods of the object. The semantics can specify when to sacri ce precise logical consistency to meet temporal consistency requirements. It can also specify accumulation and bounding of any resulting logical imprecision. We show that this technique, under certain general restrictions, can preserve global correctness and bound imprecision by proving it can guarantee a form of epsilon serializability specialized for object-oriented databases.