[5.0.1] Query: Pushdown into subquery when applying group by over a group by #23297
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Approved by Tactics for 5.0.1. |
Resolves #23265 Everyone wants their own set of conditions for pushdown. ¯\_(ツ)_/¯
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Resolves #23265
Everyone wants their own set of conditions for pushdown. ¯\(ツ)/¯
Description
When applying GroupBy over result of another GroupBy-aggregate, we missed doing a push-down of the subquery causing incorrect results. This is a regression from 3.1 in a reasonably common query pattern.
Customer Impact
Incorrect results which can cause data corruption in customer apps.
How found
Customer reported on 5.0.
Test coverage
Added test for affected scenario.
Regression?
Yes, this worked in 3.1.
Risk
Low. This brings back same set of condition which were in place for push-down in 3.1