Persistent object synchronization with active relational databases

One of the most common client/server architectures in enterprise systems today is the combination of object oriented applications with active relational database systems. With this combination, developers have to overcome a difficult problem: the impedance mismatch between object orientation and the relational model. To date, there are several incomplete approaches for describing the integration of static and dynamic object aspects and active relational databases. An important issue missing from these approaches is the state synchronization between server tuples and client cached objects. In a previous paper (A.M. Porto et al., 1998) we proposed a technique for mapping the dynamic behavior of objects into active relational databases, using database triggers and stored procedures. The paper extends our previous one with an architecture based on a replication strategy that maintains server tuples and client cached objects synchronized with respect to state. This architecture automatically updates client cached object versions when their corresponding server database tuples are updated.