Horizontal class fragmentation in distributed object based systems

Many researchers have demonstrated the importance of entity fragmentation in distributed relational database design. Database design will be essential in the `next-generation\u27 engineering design environment that exploits object-oriented technologies. Fragmentation enhances application performance by reducing the amount of irrelevant data accessed and the amount of data transferred unnecessarily between distributed sites. Algorithms for effecting horizontal and vertical fragmentation of relations exist, but fragmentation techniques for class objects in a distributed object based system have not appeared in the literature. This paper first presents a taxonomy of the fragmentation problem in a distributed object based system capable of supporting systems engineering applications. Detailed horizontal fragmentation algorithms are then presented for one of these class models using a top-down approach where the entity of fragmentation is the class object. The algorithms described incorporate the inherent features of the object model including both inheritance and class composition hierarchies