In order to reduce the disk access time, a database can be stored on several simultaneously accessi- ble disks. In this paper, we are concerned with the dynamic d-attribute database allocation problem for range querie...In order to reduce the disk access time, a database can be stored on several simultaneously accessi- ble disks. In this paper, we are concerned with the dynamic d-attribute database allocation problem for range queries. An allocation method, called coordinate modulo allocation method, is proposed to al- locate data in a d-attribute database among disks so that the maximum disk accessing concurrency can be achieved for range queries. Our analysis and experiments show that the method achieves the optimum or near-optimum parallelism for range queries. The paper offers the conditions under which the method is optimal. The worst case bounds of the performance of the method are also given. In addi- tion, the parallel algorithm of processing range queries is described at the end of the paper. The meth- od has been used in the statistic and scientific database management system which is being designed by us.展开更多
I/O parallelism is considered to be a promising approach to achieving highperformance in parallel data warehousing systems where huge amounts of data and complex analyticalqueries have to be processed. This paper prop...I/O parallelism is considered to be a promising approach to achieving highperformance in parallel data warehousing systems where huge amounts of data and complex analyticalqueries have to be processed. This paper proposes a parallel secondary data cube storage structure(PHC for short) to efficiently support the processing of range sum queries and dynamic updates ondata cube using parallel computing systems. Based on PHC, two parallel algorithms for processingrange sum queries and updates are proposed also. Both the algorithms have the same time complexity,O(log^d n/P). The analytical and experimental results show that PHC and the parallel algorithms havehigh performance and achieve optimum speedup.展开更多
文摘In order to reduce the disk access time, a database can be stored on several simultaneously accessi- ble disks. In this paper, we are concerned with the dynamic d-attribute database allocation problem for range queries. An allocation method, called coordinate modulo allocation method, is proposed to al- locate data in a d-attribute database among disks so that the maximum disk accessing concurrency can be achieved for range queries. Our analysis and experiments show that the method achieves the optimum or near-optimum parallelism for range queries. The paper offers the conditions under which the method is optimal. The worst case bounds of the performance of the method are also given. In addi- tion, the parallel algorithm of processing range queries is described at the end of the paper. The meth- od has been used in the statistic and scientific database management system which is being designed by us.
文摘I/O parallelism is considered to be a promising approach to achieving highperformance in parallel data warehousing systems where huge amounts of data and complex analyticalqueries have to be processed. This paper proposes a parallel secondary data cube storage structure(PHC for short) to efficiently support the processing of range sum queries and dynamic updates ondata cube using parallel computing systems. Based on PHC, two parallel algorithms for processingrange sum queries and updates are proposed also. Both the algorithms have the same time complexity,O(log^d n/P). The analytical and experimental results show that PHC and the parallel algorithms havehigh performance and achieve optimum speedup.