The data federation pattern supports data operations against an integrated and transient (virtual) view where the real data is stored in multiple diverse sources.

数据联合模式支持在集成的临时(虚拟)视图上进行数据操作；在此类视图中，实际数据存储在多个不同的源上。

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In San Diego, they use the data to build the virtual model of the entire fortress.

在圣地亚哥，他们用这些数据建立整个堡垒的虚拟模型。

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When there are sales performance data being tracked in different cubes, a virtual cube provides a way to have the overall view by aggregating these separate cubes.

如果需要在不同的数据集中跟踪销售绩效数据，那么通过使用虚拟数据集合并各个数据集可以获得总体视图。

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For the most part most data centers are operating in the pre-virtual world, in which the pace of change is governed by the rate at which physical servers can come and go.

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They were collected primarily through police reports in 2007, death certificates and the number of fatalities registered by the Not-in-Traffic Surveillance system, a virtual data collector of details regarding nontraffic crashes nationwide.

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They may even realise that they no longer need to make cars at all, deciding to follow the example of Cisco Systems, a data-networking firm, by becoming virtual companies whose expertise lies in design and brand marketing.

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