[branch-54] fix: clear handled OFFSET before child recursion in LimitPushdown (#22525)#22631
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[branch-54] fix: clear handled OFFSET before child recursion in LimitPushdown (#22525)#22631alamb wants to merge 1 commit into
alamb wants to merge 1 commit into
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…2525) ## Which issue does this PR close? <!-- We generally require a GitHub issue to be filed for all bug fixes and enhancements and this helps us generate change logs for our releases. You can link an issue to this PR using the GitHub syntax. For example `Closes #123` indicates that this PR will close issue #123. --> - Closes #22489. ## Rationale for this change `LimitPushdown` carries `GlobalRequirements` while walking the physical plan. In the bad plan shape from #22489, an outer `OFFSET` was already handled above a sort barrier, but its `skip` still remained in the state when recursion continued into the child subtree. That stale `skip` then merged with an inner `LIMIT` and reduced its fetch incorrectly, which caused a grouped row to be dropped. The fix is to clear `skip` once the limit requirement has already been handled, while keeping `fetch` so valid limit pushdown into child sorts still happens. <!-- Why are you proposing this change? If this is already explained clearly in the issue then this section is not needed. Explaining clearly why changes are proposed helps reviewers understand your changes and offer better suggestions for fixes. --> ## What changes are included in this PR? - Clear `skip` before recursing into children when the limit requirement is already handled. - Keep `fetch` unchanged so valid TopK-style pushdown still works. - Add a physical optimizer regression test for the exact outer `OFFSET` / sort barrier / inner `LIMIT` shape. - Add an end-to-end sqllogictest for the SQL reproducer from #22489. <!-- There is no need to duplicate the description in the issue here but it is sometimes worth providing a summary of the individual changes in this PR. --> ## Are these changes tested? Yes <!-- We typically require tests for all PRs in order to: 1. Prevent the code from being accidentally broken by subsequent changes 2. Serve as another way to document the expected behavior of the code If tests are not included in your PR, please explain why (for example, are they covered by existing tests)? --> ## Are there any user-facing changes? No API Change <!-- If there are user-facing changes then we may require documentation to be updated before approving the PR. --> <!-- If there are any breaking changes to public APIs, please add the `api change` label. -->
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54.0.0(Apr 2026 / May 2026) #21080This PR:
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