一个 XML Relational Mapping 操作符（见 图 4 下方的分支）的输出可以直接用于填充目标表。

The output from one of the XML Relational Mapping operators (shown on the lower branch of Figure 4) can feed the target table directly.

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其中一个操作符(图1中下方的分支)为一个Group By操作符提供输入，后者执行目标表的两个列所需的聚合。

One of these operators (shown on the lower branch in Figure 1) feeds a Group by operator that performs the aggregations required by two of the target table's columns.

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其中一个操作符(图4中下方的分支)为一个Group By操作符提供输入，后者执行表1中所示的聚合。

One of these operators (shown on the lower branch in Figure 4) feeds a Group By operator, which performs the aggregations shown in Table 1.

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