[enhancement](Nereids) support 4 phases distinct aggregate with full distribution #36016
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…distribution (apache#35871) The origin implementation of 4 phases distinct aggregate only support the pattern which not contains `group by`, and only one distinct aggregate function for example: ```sql select count(distinct sex), sum(age) from student ``` This pr complement the 4 phases distinct aggregate with full distribution, to avoid data skew in the `group by`. for example ```sql select sex, sum(distinct age) from student group by sex; ``` The sex only contains two distinct values, `male` and `female`, and the table store millions rows. Shuffle by the `sex` cause the data skew and lots of instances process empty rows. The 4 phase aggregate shuffle `sex, age` to distinct rows first, so more instances can do parallel distinct, the plan shape will like this: ``` PhysicalAggregate(groupBy=[sex], output=[sex, sum(partial_sum(age))], mode=BUFFER_TO_RESULT) | PhysicalDistribute(columns=[sex]) | PhysicalAggregate(groupBy=[sex], output=[sex, partial_sum(age)], mode=INPUT_TO_BUFFER) | PhysicalAggregate(groupBy=[sex, age], output=[sex, age], mode=BUFFER_TO_BUFFER) | PhysicalDistribute(columns=[sex, age]) # more columns to shuffle avoid data skew | PhysicalAggregate(groupBy=[sex, age], output=[sex, age], mode=INPUT_TO_BUFFER) | PhysicalOlapScan(name=student) ``` (cherry picked from commit 03f1cbd)
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cherry pick from #35871