对于该新功能，需要在消息描述符中附加字段来保留分段和分组信息。

For this new function, additional fields in message descriptor were needed to keep information for the segmenting and grouping.

youdao

有了分组信息之后，我们就可以识别出正确的聚集信息，并计算最终应该返回的结果。

With the group information, we can identify the correct aggregation information and calculate the final result that shall be returned.

youdao

现在，我们可从当前分组（或一个新开始的分组）中获得聚集信息，并将分组信息和传递给 UDF 的参数结合起来。

Now we get the aggregation information for the current group (or start a new group) and combine that group information with the parameters that were passed in to the UDF.

youdao