Fix MATERIALIZE INDEX/PROJECTION mutation stuck after DROP#98369
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alexey-milovidov merged 2 commits intomasterfrom Mar 1, 2026
Merged
Fix MATERIALIZE INDEX/PROJECTION mutation stuck after DROP#98369alexey-milovidov merged 2 commits intomasterfrom
alexey-milovidov merged 2 commits intomasterfrom
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…n is dropped `MATERIALIZE INDEX` and `MATERIALIZE PROJECTION` mutations could get stuck with "Unknown index" or "No such projection" exceptions if the index or projection was dropped before the mutation finished executing. This can happen in replicated environments or after `KILL MUTATION` followed by `DROP INDEX`/`DROP PROJECTION`. The fix makes `MutationsInterpreter::prepare` gracefully skip materialization when the target index or projection no longer exists in the metadata, instead of throwing an exception. Closes #38643 ### Changelog category: - Bug Fix (user-visible misbehavior in an official stable release) ### Changelog entry: Fix `MATERIALIZE INDEX` and `MATERIALIZE PROJECTION` mutations getting stuck when the index or projection is dropped before the mutation finishes. Co-Authored-By: Claude Opus 4.6 <[email protected]>
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This looks alright.
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Hi — this PR may need backporting to release branches Why: This fixes stuck mutations (issue #38643 from 2022) in MutationsInterpreter, which is core MergeTree code present in all stable branches. The bug affects both replicated and non-replicated tables and can block mutation progress indefinitely. If this should be backported, consider adding |
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Summary
MATERIALIZE INDEXandMATERIALIZE PROJECTIONmutations getting stuck with "Unknown index" / "No such projection" exceptions when the index or projection is dropped before the mutation finishes executingKILL MUTATIONfollowed byDROP INDEX/DROP PROJECTIONMutationsInterpreter::preparegracefully skip materialization when the target no longer exists, instead of throwingCloses #38643
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Changelog entry:
Fix
MATERIALIZE INDEXandMATERIALIZE PROJECTIONmutations getting stuck when the index or projection is dropped before the mutation finishes.🤖 Generated with Claude Code