为了使列存储OLAP(on-line analytical processing)操作中I/O和CPU开销较大的扫描、连接、聚集操作实现有效的共享和复用,提出了一个多查询优化技术。根据列存储以及OLAP操作的特点,提出了一系列转换规则,为OLAP查询请求产生的一组相关...为了使列存储OLAP(on-line analytical processing)操作中I/O和CPU开销较大的扫描、连接、聚集操作实现有效的共享和复用,提出了一个多查询优化技术。根据列存储以及OLAP操作的特点,提出了一系列转换规则,为OLAP查询请求产生的一组相关查询语句生成一个单一全局查询计划。为了达到共享复用的目的,在全局计划中引入新的过滤结点、分组结点、合并结点和聚集结点。同时,借用MuGA(multiply group by algo-rithm)算法,通过分组结点、合并结点、连接结点实现维表及事实表元组的分组序号标记,从而实现列扫描、列连接的共享。并为聚集结点提出了一个多阶段聚集算法,结合最终生成的事实表复合分组序号,实现聚集操作的复用。在SSB(star schema benchmark)数据集上设计实验,证明了该多查询优化策略的有效性。展开更多
Objective: To study the basic prescriptions of drugs and points for point application in summer to treat the diseases with attacks in winter and the law governing their compatibility. Methods: A database was set up by...Objective: To study the basic prescriptions of drugs and points for point application in summer to treat the diseases with attacks in winter and the law governing their compatibility. Methods: A database was set up by collecting and sorting out the relevant literature, and the analysis was made with the complex network. Results: It was found that Bai Jie Zi (白芥子 Semen Sinapis Albae), Xi Xin (细辛 Herba Asari), Gan Sui (甘遂 Radix Euphorbiae Kansui) and Yan Hu Suo (延胡索 Rhizoma Corydalis) were used as the basic prescriptions of drugs, Feishu (BL 13), Dazhui (GV 14) and Shanzhong (CV 17) were selected as the basic prescription of points. Conclusion: The knowledge obtained from the complex networks on the basic prescriptions of drugs and points for point-application in summer to treat diseases with attacks in winter can provide a data support for working out operation norms and carrying on verification research.展开更多
文摘为了使列存储OLAP(on-line analytical processing)操作中I/O和CPU开销较大的扫描、连接、聚集操作实现有效的共享和复用,提出了一个多查询优化技术。根据列存储以及OLAP操作的特点,提出了一系列转换规则,为OLAP查询请求产生的一组相关查询语句生成一个单一全局查询计划。为了达到共享复用的目的,在全局计划中引入新的过滤结点、分组结点、合并结点和聚集结点。同时,借用MuGA(multiply group by algo-rithm)算法,通过分组结点、合并结点、连接结点实现维表及事实表元组的分组序号标记,从而实现列扫描、列连接的共享。并为聚集结点提出了一个多阶段聚集算法,结合最终生成的事实表复合分组序号,实现聚集操作的复用。在SSB(star schema benchmark)数据集上设计实验,证明了该多查询优化策略的有效性。
基金supported by the National Basic Research Program of China (No. 2006CB504601) the National Key Technology R&D Program (No. 2008BA53B00)
文摘Objective: To study the basic prescriptions of drugs and points for point application in summer to treat the diseases with attacks in winter and the law governing their compatibility. Methods: A database was set up by collecting and sorting out the relevant literature, and the analysis was made with the complex network. Results: It was found that Bai Jie Zi (白芥子 Semen Sinapis Albae), Xi Xin (细辛 Herba Asari), Gan Sui (甘遂 Radix Euphorbiae Kansui) and Yan Hu Suo (延胡索 Rhizoma Corydalis) were used as the basic prescriptions of drugs, Feishu (BL 13), Dazhui (GV 14) and Shanzhong (CV 17) were selected as the basic prescription of points. Conclusion: The knowledge obtained from the complex networks on the basic prescriptions of drugs and points for point-application in summer to treat diseases with attacks in winter can provide a data support for working out operation norms and carrying on verification research.
