An iterator is a kind of code helper that lets you quickly access data in any collection or container, one at a time.

迭代器是某种代码助手，可以让您迅速地访问任何集合或容器中的数据，每次一个数据。

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A query is a collection of counters, created in your custom code, to manage the collection of performance data.

查询是计数器的集合，它是用自定义代码创建的，用于管理性能数据的集合。

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The Rational PurifyPlus product has three components: Purify for memory error checking, Quantify for performance data collection, and PureCoverage for code-coverage analysis.

Rational PurifyPlus产品有三个组件：内存错误验证的Purify，性能数据采集的Quantify，以及代码覆盖分析的PureCoverage。

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For example, when a user visited a website that had code for one tracking technology, the data collection would call out to and trigger other tracking technologies that weren't embedded on the site.

WSJ: Online Tracking Increases, Fueled by Ad Auctions