公开(公告)号：US09158812B2

公开(公告)日：2015-10-13

申请号：US13754740

申请日：2013-01-30

Applicant: Oracle International Corporation

Inventor： Huagang Li ,  Srikanth Bellamkonda

IPC: G06F7/00 ,  G06F17/30

CPC classification number: G06F17/30445

Abstract: According to one aspect of the invention, for a database statement that specifies evaluating ranking or cumulative window functions, an execution strategy based on an extended data distribution key may be used for the database statement. In the execution strategy, each sort operator of multiple parallel processing sort operators computes locally evaluated results of a ranking or cumulative window function based on a subset of rows in all rows used to evaluate the database statement, and sends the first and last rows' locally evaluated results to a query coordinator. The query coordinator consolidates the locally evaluated results received from the multiple parallel processing sort operators and sends consolidated results to the sort operators based on their respective demographics. Each sort operator completes full evaluation of the ranking or cumulative window functions based at least in part on one or more of the consolidated results provided by the query coordinator.

Abstract translation: 根据本发明的一个方面，对于指定评估排名或累积窗口函数的数据库语句，可以对数据库语句使用基于扩展数据分配密钥的执行策略。 在执行策略中，多个并行处理排序运算符的每个排序运算符基于用于评估数据库语句的所有行中的行的子集来计算排名或累积窗口函数的本地评估结果，并将第一行和最后一行“ 评估结果给查询协调器。 查询协调器整合从多个并行处理排序运算符接收的本地评估结果，并根据各自的人口统计特征将综合结果发送给排序运算符。 每个排序运算符至少部分地基于查询协调器提供的一个或多个综合结果完成对排名或累积窗函数的完全评估。