At a large retailer, adding a missing index to a small, 2,000-row table in an 8 TB warehouse reduced the elapsed time of a critical decision support query from three hours to two minutes.

在一家大型零售商的8 TB数据仓库中，在一个2,000行的小表上添加一个索引之后，一个决策支持查询花费的时间从三小时一下降到了两分钟。

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For example, consider a federated union query across three sources.

例如，考虑一个跨三个数据源的联邦联合查询。

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As you can see, the query was executed three times, and the average elapsed time is about 307 seconds, which is very slow.

如您所见，查询执行了三次，平均运行时间大约是307秒，非常慢。

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James was coy about this last query, saying only that she has three unnamed actors in mind for Christian and four in mind for Anastasia.

CNN: STORY HIGHLIGHTS

After the Russian government made its 2011 query on Mr. Tsarnaev, the FBI three times requested more information and received none, U.S. officials say.

WSJ: U.S.: Russia Withheld Intel on Boston Bomb Suspect

Mr. WHITAKER: You could do a query to identify all parcels with a particular zoning designation within so many feet of three-phase electrical power and so many feet of a water line, and the three properties left to put your business or your school would light up.

NPR: Security Officials Seek to Block Some Online Maps