fix(replace): handle one new row conflicting with multiple old rows via different unique keys#24581
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…ia different unique keys REPLACE INTO raised a duplicate-key error when a single new row conflicted with several existing rows through different unique keys (issue matrixorigin#24428). The expected MySQL semantics are: delete all conflicting old rows, then insert the new row once. Root causes and fixes: 1. hashbuild (real PK + multi-UK): the OR'd LEFT JOIN fans one new row into several build rows carrying different old PKs. keep-last keeps one and turns the rest into delete-only rows, but their old-PK column was nulled and the delColIdx delete-marker pass only scanned surviving rows, so the surviving bucket was not marked deleted. When the new PK also matched an existing row, the dedup-join probe then raised a false DuplicateEntry. Preserve the old-PK column on delete-only rows and scan them in the delColIdx pass. 2. bind_replace (fake PK): fake-PK tables built the conflict-detection LEFT JOIN from only the first unique key, missing conflicts on the others. OR one condition per unique key, matching the real-PK path. Adds a hashbuild unit test for the discarded-fan-out delete marking and BVT coverage for multi-UK / explicit-PK+multi-UK / fake-PK / composite-UK fan-out. Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
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heni02
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This follow-up completes the REPLACE multi-unique-key fan-out path: it preserves the old-PK value on delete-only rows, scans the full build batch when marking delete buckets, and adds unit/BVT coverage for the previously failing fan-out cases.
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XuPeng-SH
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I checked the multi-UK fan-out fix from a few angles: the fake-PK LEFT JOIN now matches conflicts on any unique key, the hashbuild keep-last path now preserves/scans the old-PK values needed to mark surviving conflict buckets as deleted, and the new unit/BVT coverage matches the previously failing REPLACE cases. The change looks consistent with the existing delete-only / DelRows / dedup-join flow.
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What type of PR is this?
Which issue(s) this PR fixes:
issue #24428
What this PR does / why we need it:
REPLACE INTOproduced a duplicate-key error when a single new row conflicted withmultiple existing rows via different unique keys. The expected MySQL semantics are:
delete all conflicting old rows, then insert the new row exactly once.
This fixes two cases:
Real PK + multiple unique keys (
pkg/sql/colexec/hashbuild/hashmap.go)The OR'd LEFT JOIN fans one new row into several build rows that carry different
old PKs.
keep-lastkeeps one of them and converts the rest into delete-only rows,but their old-PK column was nulled and the
delColIdxdelete-marker pass onlyscanned the surviving rows. So the surviving bucket was not marked deleted, and when
the new PK also matched an existing row the dedup-join probe raised a false
Duplicate entry. Fix: keep the old-PK column on the delete-only rows and let thedelColIdxpass scan them, so the surviving bucket is correctly marked deleted.Fake PK + multiple unique keys (
pkg/sql/plan/bind_replace.go)Fake-PK tables built the conflict-detection LEFT JOIN from only the first unique
key, missing conflicts on the others. Fix: OR one (AND-of-parts) condition per unique
key, matching the real-PK path.
The single-UK fix (#24425) and the duplicate-source-key keep-last behavior (#24497) are
preserved.
How verified
TestDedupBuildKeepLastMarksConflictBucketForDiscardedFanout(fails without the fix, passes with it).
test/distributed/cases/dml/replace/replace.{test,result}coveringmulti-UK / explicit-PK + multi-UK / fake-PK / composite-UK / multi-row fan-out.
multi_update unit tests pass;
make static-checkis clean.🤖 Generated with Claude Code