Files
doris/regression-test
minghong a6d2013802 [opt](nereids) use 2 phase agg above union all (#26245)
forbid one phase agg for pattern: agg-unionAll
one phase agg plan: agg-union-hashDistribute-children
two phase agg plan: agg(global) - hashDistribute-agg(local)-union-randomDistribute
the key point is the cost of randomDistribute is much lower than the hashDistribute, and hence two-phase agg wins.
2023-11-08 17:15:53 +08:00
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