【作者】 宋宝燕； 陆岩； 张俊宁；

【Author】 Song Baoyan,Lu Yan,and Zhang Junning (School of In formation Science and Technology,Liaoning University,Shenyang 110036)

【机构】 辽宁大学信息科学与技术学院；

【摘要】 针对数据流系统中的查询处理机制进行了深入的研究,从内存使用量和查询的实时性两方面进行综合考虑,提出了一种适应性查询优化策略Slope.该策略一方面可以根据各操作符的选择度和单位时间处理元组个数来适时调整查询计划;另一方面可以按调整后的查询计划进行非等值时间片轮转调度.还给出了Slope策略的相应算法并进行了性能测试.更多还原

【Abstract】 In this paper query processing mechanisms in the data stream system are discussed and a dynamic optimum strategy based on both memory and response time is proposed.This strategy decides a query plan by operator’s selectivity and the number of tuples which it processes in every time unit.And then it accords this plan to scheduling.This paper also gives the algorithm of slope strategy.And then some experiments are conducted to prove this strategy is better than others.更多还原