E.M. Boertjes

Database Support for Workflow Management

From the Publisher: Database Support for Workflow Management: The WIDE Project presents the results of the ESPRIT WIDE project on advanced database support for workflow management. The book discusses the state of the art in combining database management and workflow management technology, especially in the areas of transaction and exception management. This technology is complemented with a high-level conceptual workflow model and associated workflow application design methodology. Database Support for Workflow Management: The WIDE Project serves as an excellent reference, and may be used for advanced courses on database and workflow management systems.

Semantics and architecture of global transaction support in workflow environments

We present an approach to global transaction management in workflow environments. The transaction mechanism is based on the well-known notion of sagas, but extended to deal with arbitrary process structures including cycles and savepoints that allow partial compensation. We present a formal specification of the transaction model and transaction management mechanisms in set and graph theory, providing clear, unambiguous transaction semantics. The specification is straightforwardly mapped to a modular architecture, the implementation of which is applied in the prototype of a commercial workflow management system. The loosely-coupled nature of the resulting system allows easy distribution using middleware technology.

An Architecture for Nested Transaction Support on Standard Database Systems

Many applications dealing with complex processes require database support for nested transactions. Current commercial database systems lack this kind of support, offering flat, non-nested transactions only. This paper presents a three-layer architecture for implementing nested transaction support on a commercial multi-database environment. The architecture is directed at high portability and flexibility. The modular approach and the simple, event driven interfaces between the layers of the architecture enable the nested transaction support to be adapted to various applications, nested transaction models and database management systems. The architecture has been implemented to support a prototype of a commercial next-generation workflow management system.

Distributed Global Transaction Support for Workflow Management Applications

Workflow management systems require advanced transaction support to cope with their inherently long-running processes. The recent trend to distribute workflow executions requires an even more advanced transaction support system that is able to handle distribution. This paper presents a model as well as an architecture to provide distributed advanced transaction support. Characteristic of the transaction support system is the ability to deal with arbitrary distribution of business processes over multiple workflow management systems and the support for flexible rollbacks. The modularity of the architecture and the orthogonality with respect to the workflow management system allows the transaction system to be applied in other application areas as well. The high scalability of the architecture allows an arbitrary combination of transaction support systems and workflow management systems of which the locations are irrelevant. In the WIDE project, the developed technology is applied to the commercial FORO workflow management system.