移动对象数据库预测范围聚集查询技术研究

针对预测范围聚集查询处理技术，提出了一种面向移动对象的聚集TPR树索引。聚集TPR树索引在TPR树中间节点中加入移动对象聚集信息以减少预测范围聚集查询所需要的节点访问代价。并增加了一个建于移动对象标识上的哈希辅助索引结构以支持自底向上的删除搜索算法，具有很好的动态更新性能和并发性。提出了一种EPRA查询算法，采用更精确的剪枝搜索准则，大大减少了查询所需要访问的磁盘节点，具有良好的查询性能。

A Novel Prediction Technique for Range Aggregation of Moving Objects

To efficiently process predictive range aggregate (PRA)queries, this paper presents a novel aggregate TPR-tree (aTPR-tree)for range aggregation of moving objects. aTPR-tree is based on TPR-tree structure and added with aggregate information in intermediate nodes to reduce the disk accesses of PRA queries. aTPR-tree is supplemented by a hash index on identifier of moving objects, and uses bottom-up delete algorithm, thus having a good update performance and concurrency. Also an Enhanced predictive range aggregate (EPRA)query algorithm which uses a more precise branch and bound searching strategy is developed, thus reducing the disk I/O greatly and having a good performance.