Don't use Finalize GroupAggregate if the input is not sorted - #10359
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Don't use Finalize GroupAggregate if the input is not sorted#10359akuzm wants to merge 1 commit into
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When we have to re-sort all input, it's inferior to hash aggregation, so don't use it. Also try hash-based partial aggregates before we try group-based ones. If they have same cost and pathkeys, only the first one survives. The hash aggregation can be disabled with a GUC and group aggregation cannot, so this makes the plan tuning more flexible.
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When we have to re-sort all input, it's inferior to hash aggregation, so don't use it.
Also try hash-based partial aggregates before we try group-based ones. If they have same cost and pathkeys, only the first one survives. The hash aggregation can be disabled with a GUC and group aggregation cannot, so this makes the plan tuning more flexible.