Concurrency Control and Recovery for Transactions in Cooperative Design Environments

Non-standard database applications like design environments or office automation require advanced transaction concepts. The inability of traditional transactions [2] to support such applications has already been observed by [6] and was the motivation for the development of a number of non-standard transaction models (for an overview, see [1] or [5]). Our work focuses on transaction management in cooperative design environments. We present a configurable and extensible transaction model called PODEST (“Programmable Object-oriented Design Transaction System”) which supports flexible mechanisms for concurrency control, cooperation and recovery. The model relies on an object-oriented database management system (OODBMS) compliant with the ODMG standard [3] and is embedded into the programming language as a class library. It offers the programmer uniform access to the OODBMS and the design transaction management. By specializing the provided classes and writing application-specific methods, it is possible to adapt the transaction model to the specific needs of the concrete design environment.