Multi-User Concurrent Design Databases

Developing comprehensive computer models of engineering systems is an important research effort. These models are planned to support design, analysis, optimization and production of these systems by providing a common integrated source of data. They are also expected to support multiple users accessing them concurrently so that parallel development of the system is enabled. This paper looks at the concurrency control problem in computer models of engineering design. It reviews the major aspects of database systems which are the tools of modelling, and identifies different representations used in the design process. With this as the context, the paper surveys the basic mechanisms for concurrency control in database systems. It then classifies the different degrees of concurrency in different representations of the design proces