Like the counting function, when several aggregations with grouping keys are used in a rule, the group and count operations must be cascaded as shown in figure 14.

与计数函数类似，当在一个规则中使用多个具有分组关键字的聚合，对分组与计数操作必须进行级联，如图14所示。

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But if you use multiple aggregations with the same grouping keys, or multiple counting functions that count the same column, it will not significantly increase the execution time of the rule.

但是，如果使用具有相同分组关键字的多个聚合，或者对相同列进行计数的计数函数，其不会显著增加规则的执行时间。

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Similarly, there is also a rule for counting the expenses made by the firm. Expenses are not counted unless the amount of expense is actually paid by the company.

确认公司的费用也适用同样的原则，发生的费用只有在实际支付时才予以确认。

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Other important counting tools include: the slide rule, the calculator, the tally stick.

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There were only two, 1990-91 and 2000-01, the latter not even counting as a recession by the old rule of needing two consecutive quarters of negative growth.

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Courts have ruled against schools that have tried to designate cheerleading as a sport for purposes of counting male and female athletes under the federal rule.

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