FETCH(3)的结果集是根据ID字段排序的，并且使用T1的索引I1的合并联接而得到最终的结果集。

The result set from FETCH (3) is ordered by the ID column and joined using a merge join with index I1 for T1 to get final result set.

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图22显示了使用Concat功能联接为单个字段的两个字段。

Figure 22 shows two fields using the Concat function to join into one single field.

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确保表与表之间相互联接的字段具有相同的数据类型和大小。

Ensure that joined fields between tables are of the same data type and size.

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