[GitHub] [doris] morrySnow commented on a diff in pull request #18423: [enhancement](Nereids) use two phase aggregate if group by key is not unique

["morrySnow (via GitHub)" <gi...@apache.org>]

morrySnow commented on code in PR #18423:
URL: https://github.com/apache/doris/pull/18423#discussion_r1160435287


##########
fe/fe-core/src/main/java/org/apache/doris/nereids/rules/implementation/AggregateStrategies.java:
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@@ -734,24 +734,24 @@ inputToBufferParam, maybeUsingStreamAgg(connectContext, logicalAgg),
      *
      * after:
      *
-     *  single node aggregate:
+     *  anyLocalGatherGlobalAgg:

Review Comment:
   the first agg must after distribution. our normal count function do not have the ability of distinct. the distinct complished by group by [name, id]. so we must shuffle all tuples with same name into one partition, and then do group by [name, id] to get unique id list of same name.



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