使用多个本地和全局聚合操作优化包含聚合表达式的sql查询

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【标题】使用多个本地和全局聚合操作优化包含聚合表达式的sql查询

【发明人】 Ramesh  Bhashyam  Kraus  Timothy Brent  Walter  Todd Allan 

【公开日期】1999-03-16

【分类号】G06F 1730

【摘要】A method, apparatus, and article of manufacture for optimizing SQL queries in a relational database management system involving aggregate and grouping functions. A local aggregation operation is performed on one or more processors of a massively parallel processor (MPP) computer system, wherein rows of the table that are local to each processor are locally aggregated to create one or more aggregate result rows. The aggregate result rows created by each of the local aggregation operations are then re-distributed to one or more processors and coalesced into a global aggregate result row by a global aggregation operation.

【申请号】7951140

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