This paper proposes a scheme for vertical partitioning of a database at the design cycle. When a partition is formed, attributes are divided among various systems or even throughout different geographical locations. This may result in situations where a query may include attributes that are located at different sites. The scheme determines the hit ratio of a partition. As long as it falls below a predetermined threshold, the partition is altered. Although no proof is provided, experimental data showed that moving an attribute that is loosely coupled to a different subset within a partition improves hit ratio. A simulator was built to test the proposed algorithm. Results of various simulation runs are consistent with the hypothesis. That is, the proposed algorithm enables a reliable distribution of newly designed database tables across multiple storage devices based on a predetermined hit ratio. The scheme is independent of frequencies of queries thus, can be used as a stepping stone for its counterpart, the dynamic partitioning technique.

This work presents the application of theory revision to the design of distributed databases to automatically revise a heuristic-based algorithm (called analysis algorithm) through the use of the FORTE system. The analysis algorithm decides the fragmentation technique to be used in each class of the database and its Prolog implementation is provided as the initial domain theory. Fragmentation schemas...

Users of distributed database systems often observe performance problems such as unexpectedly low throughput or high latency. Determining the cause of the performance problems can be very hard task. Bottlenecks can occur in any of the components through which the data flows: the applications, the operating systems, the network interfaces and hardware. Horizontal and vertical partitioning are important aspects of physical design in relational database system that has a significant impact on performance. The distribution design involves making decisions on the fragmentation and the allocation of data across the sites of a computer network. In this paper we address the fragmentation phase of distributed database systems. In this paper, vertical partitioning problem during the design of distributed databases is discussed by conducting a comparative study for different vertical partitioning algorithms to reach the most efficient vertical fragmentation scheme that leads to a proper data allocation and replication.