Supporting Distributed Query Processing in a Heterogeneous Environment

To make effective use of distributed systems acting together to form a virtual enterprise, global coordinated operations must be possible. Such operations may be mere queries or complex update operations. In this paper, we describe an existing system at the University of Florida which not only models a Virtual Enterprise using a common object-oriented semantic association model, but acts as a trader and repository for common information. The primary objective of this paper is to show how this existing system is being extended to handle complex global operations stated in the form of Object Query Language queries. These queries are then processed in a distributed manner, including any necessary object migrations. Problems addressed in this paper include: provision of support information in the meta-model, allocation of global object instance identifiers, issuing and coordination of subqueries to the legacy systems in the Virtual Enterprise, and the issuing and coordination of method executions.