摘要
并行数据库查询优化的关键是缩减庞大的计划搜索空间,针对无共享结构(SN),充分考虑通信开销,给出代价估计模型,采用两阶段优化方法,依据代价估计模型先对查询树进行顺序优化,并提出一种新的两阶段查询优化策略.对顺序优化的查询计划进行并行化,充分利用了多处理机的并行性,获得了较快的查询响应速度,既具备良好的并行性又避免了复杂性.
The aim of the study is to prune the big search space to optimize query techniques for parallel databases. Taking communication costs into account, a cost-evaluated model based on shared-nothing structure was proposed. With the model, two-phased optimization strategy was used to optimize the query tree sequentially, and the sequential optimization tree was parallelized in the second phase. After parallelization of multi-processors was used, faster response-time was acquired. The good parallelization was achieved and the complexity was avoided by the new strategy.
出处
《华中科技大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2006年第3期11-13,20,共4页
Journal of Huazhong University of Science and Technology(Natural Science Edition)
关键词
并行数据库
查询优化
两阶段优化
parallel database
query optimization
two-phased optimization
