opt: don't use outer columns as implicit grouping columns#68678
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craig[bot] merged 1 commit intocockroachdb:masterfrom Aug 17, 2021
Merged
opt: don't use outer columns as implicit grouping columns#68678craig[bot] merged 1 commit intocockroachdb:masterfrom
craig[bot] merged 1 commit intocockroachdb:masterfrom
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Previously, the optbuilder logic would add any outer column that is referenced in a grouping context to the set of grouping columns. This is correct in some cases, because outer columns are effectively constant, and can just be removed by norm rules. However, it is incorrect in the case when there are no grouping columns, e.g. a `ScalarGroupBy`. In that case, the `ScalarGroupBy` would inadvertently be converted into a `GroupBy`. This patch modifies the optbuilder to simply ignore outer columns in a grouping context. Fixes cockroachdb#68290 Release note: None
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mgartner
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Aug 11, 2021
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Nice!
You might want to wait for Radu to take a look though - I'm not super familiar with this part of the code.
Reviewed 2 of 2 files at r1, all commit messages.
Reviewable status:complete! 1 of 0 LGTMs obtained (waiting on @RaduBerinde)
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@RaduBerinde mind taking look when you have time? |
RaduBerinde
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Aug 17, 2021
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No worries! This is pretty low-priority |
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TFTRs! |
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bors r+ |
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Build succeeded: |
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Previously, the optbuilder logic would add any outer column that is
referenced in a grouping context to the set of grouping columns. This
is correct in some cases, because outer columns are effectively constant,
and can just be removed by norm rules. However, it is incorrect in the
case when there are no grouping columns, e.g. a
ScalarGroupBy. In thatcase, the
ScalarGroupBywould inadvertently be converted into aGroupBy.This patch modifies the optbuilder to simply ignore outer columns in a
grouping context.
Fixes #68290
Release note: None