branch-4.1:[fix](fe) Fix redundant aggregation in agg-union query plan #62231#63577
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…2231) When multiple grouped queries are combined via UNION ALL on randomly distributed tables without PhysicalDistribute operators, Doris was generating redundant local aggregation and global aggregation layers without a distribute operator between them. The issue was in the `banAggUnionAll` method in ChildrenPropertiesRegulator, which was too aggressively forbidding one-phase aggregation for all agg-union patterns, regardless of whether the union inputs had PhysicalDistribute operators. Modified the `banAggUnionAll` method to only forbid one-phase aggregation when the union inputs actually have PhysicalDistribute operators: 1. Checks each group in the union 2. Examines all physical expressions in each group 3. Only forbids one-phase agg if any input has PhysicalDistribute 4. Allows one-phase agg if no inputs have PhysicalDistribute Added regression test `agg_union_group_by.groovy` to verify correct behavior Improved query optimization: Eliminated redundant aggregation layers in UNION ALL queries with GROUP BY on randomly distributed tables.
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yiguolei
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May 25, 2026
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picked from #62231