Fix fatal exception in loadDataPart for parts with outdated TIDs#96866
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alexey-milovidov merged 1 commit intomasterfrom Feb 14, 2026
Merged
Fix fatal exception in loadDataPart for parts with outdated TIDs#96866alexey-milovidov merged 1 commit intomasterfrom
alexey-milovidov merged 1 commit intomasterfrom
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During part loading, `getCSNAndAssert` throws a fatal LOGICAL_ERROR when encountering a part whose creation TID has been cleaned up from the transaction log (tail_ptr moved past the TID's start_csn). This happens when a merge transaction fails (e.g., on an Ordinary database that doesn't support transactions) and leaves a part on disk with a TID that was never committed. As other transactions advance the log, the cleanup thread moves tail_ptr past the stale TID. Replace `getCSNAndAssert` with `getCSN` in `loadDataPart` for both creation and removal TIDs. When `getCSN` returns `UnknownCSN` for an outdated TID, the existing code correctly treats the part as from a rolled-back transaction (`RolledBackCSN`), marking it as outdated for removal. This is safe because if the transaction had been committed, its CSN would have been persisted to the part's metadata before the log entry was cleaned up. Fixes the server crash triggered by test `03915_intersecting_parts_rollback` from PR #96635. https://s3.amazonaws.com/clickhouse-test-reports/json.html?REF=master&sha=e9b4a584c40ec53b02093d24df92975e0d72c87f&name_0=MasterCI&name_1=Stateless%20tests%20%28arm_binary%2C%20parallel%29&name_1=Stateless%20tests%20%28arm_binary%2C%20parallel%29 Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Summary
Trying to get CSN for too old TID) that shows up duringATTACH TABLEwhen loading parts with outdated TIDs from rolled-back transactionsgetCSNAndAssertwithgetCSNinloadDataPartfor both creation and removal TID lookups — the existing code already correctly treats unknown CSNs as rolled-back transactions03915_intersecting_parts_rollbackfrom PR Fix intersecting parts on disk from rolled-back merge transactions #96635, where failed merge transactions on an Ordinary database leave parts with stale TIDs that get cleaned up from the transaction log by other concurrent transactionsCI report: https://s3.amazonaws.com/clickhouse-test-reports/json.html?REF=master&sha=e9b4a584c40ec53b02093d24df92975e0d72c87f&name_0=MasterCI&name_1=Stateless%20tests%20%28arm_binary%2C%20parallel%29&name_1=Stateless%20tests%20%28arm_binary%2C%20parallel%29
Test plan
03915_intersecting_parts_rollbackshould pass without crashing the serverChangelog category (leave one):
Changelog entry (a user-readable short description of the changes that goes into CHANGELOG.md):
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