Fix index oob panic in unparser with mismatched stacked projections#21094
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friendlymatthew wants to merge 1 commit intoapache:mainfrom
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Fix index oob panic in unparser with mismatched stacked projections#21094friendlymatthew wants to merge 1 commit intoapache:mainfrom
friendlymatthew wants to merge 1 commit intoapache:mainfrom
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friendlymatthew
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Mar 21, 2026
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self review
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| if outer_projections.expr.len() != inner_projection.expr.len() { | ||
| return (plan, vec![]); | ||
| } | ||
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can confirm that when I remove this, the test below will panic
adriangb
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Mar 21, 2026
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👍🏻 this fixes a runtime panic (very bad) and causes no other test regressions
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Rationale for this change
This PR adds a length guard in
subquery_alias_inner_query_and_columnsto prevent a panic when outer and inner projections have different expression countsWithout this fix, optimizer passes like
CommonSubexprEliminatecan produce stacked projections where the inner projections has more exprs than the outer. The function iterates overinner_projection.exprby index and uses the same index to accessouter_projections.expr, causing an index oob panicThis PR bails out early when the lengths don't match. This is consistent with all the other early returns in the function that reject non-matching plan shapes