Introduction Traditionally, real-time systems manage their data (e.g., chamber temperature, aircraft locations) in application-dependent structures. As real-time systems evolve, their applications become more complex and require access to more data. It thus becomes necessary to manage the data in a systematic and organized fashion. Database management systems provide tools for such organization, so in recent years there has been interest in "merging" database and real-time technology. The resulting integrated system, which provides database operations with real-time constraints, is generally called a real-time database system (RTDBS) [1]. Like a conventional database system, a RTDBS functions as a repository of data, provides efficient storage, and performs retrieval and manipulation of information. However, as a part of a real-time system, whose "tasks" are associated with time constraints, a RTDBS has the added burden of ensuring some degree of 1 This chapt