Deduplicate reduce aggregations #3881
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frankmcsherry
commented
Aug 6, 2020
benesch
approved these changes
Aug 6, 2020
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The aggregations in
Reducemay contain duplicates, notably in the case thatavgresults in multiple counts of non-nullable columns, which yields severalcount(*)aggregates. This PR removes any duplicates and uses a projection to copy the column references around.This change is