2025 Changelog

ClickHouse release v25.11.4.19-stable (2c64eff7334) FIXME as compared to v25.11.3.54-stable (2199c84bef3)

Backward Incompatible Change

• Backported in #92120: Follow-up to https://github.com/ClickHouse/ClickHouse/pull/88380. This PR marks disabled positional arguments in the projections as a backward-incompatible change. Additionally, it introduces the enable_positional_arguments_for_projections setting to enable a safe ClickHouse cluster upgrade when positional arguments are present in the projections. #92007 (Dmitry Novik).

Improvement

• Backported in #92571: Make query memory usage detection for spilling to disk during aggregation/sorting more robust. #92500 (Azat Khuzhin).

Bug Fix (user-visible misbehavior in an official stable release)

• Backported in #92530: Fix possible logical error in Log engine during subcolumns reading. Closes #91710. #91711 (Pavel Kruglov).
• Backported in #92256: Add repair mechanism for JSON with duplicated path in shared data and dynamic paths that could happen because of the bug that was fixed in https://github.com/ClickHouse/ClickHouse/pull/90816. #91886 (Pavel Kruglov).
• Backported in #92555: Cache schema only for the file it was inferred from in globs instead of all files during schema inference. Closes #91745. #92006 (Pavel Kruglov).
• Backported in #92683: Release request stream in insert select to prevent closing http connection. #92175 (Sema Checherinda).
• Backported in #92707: Fix count_distinct_optimization pass over window functions and over multiple arguments. #92376 (Raúl Marín).
• Backported in #92431: Fix possible crash in aggregate functions after MEMORY_LIMIT_EXCEEDED. #92390 (Azat Khuzhin).
• Backported in #92674: Inherit source part serialization info settings during mutation in MergeTree. It fixes possible incorrect result of the query over mutated part after changes in data types serialization. #92419 (Pavel Kruglov).
• Backported in #92622: Fix deadlock for SHOW CREATE DATABASE for Backup database. #92541 (Azat Khuzhin).
• Backported in #92665: Prevent crash in tokens() with null second argument. #92586 (Raúl Marín).
• Backported in #92743: Fix bug in data skipping logic when not match(...) is used in WHERE causing incorrect results. Closes #92492. #92726 (Nihal Z. Miaji).
• Backported in #92771: Do not attempt to delete temporary directories at startup if a MergeTree table is created over a read-only disk. #92748 (Alexey Milovidov).
• Backported in #92803: Fix "Cannot add action to empty ExpressionActionsChain" for ALTER TABLE REWRITE PARTS (v2). #92754 (Azat Khuzhin).

Build/Testing/Packaging Improvement

• Backported in #92471: Use any of chcache and sccache as rust wrapper. #92404 (Mikhail f. Shiryaev).

NOT FOR CHANGELOG / INSIGNIFICANT

• Backported in #92450: Fix polaris catalog: encode nested namespace. #92079 (Konstantin Vedernikov).
• Backported in #92824: Change log level. #92810 (Konstantin Vedernikov).
• Move enable_positional_arguments_for_projections into 25.11 in settings history. #92841 (Azat Khuzhin).