Changelog 2026

- Fix possible conflict in column and subcolumn with the same name leading in using wrong serialization and query failures. Closes [#90219](https://github.com/ClickHouse/ClickHouse/issues/90219). Closes [#85161](https://github.com/ClickHouse/ClickHouse/issues/85161). [#92453](https://github.com/ClickHouse/ClickHouse/pull/92453) ([Pavel Kruglov](https://github.com/Avogar)).
- Fix a `LOGICAL_ERROR`s that caused by not wanted modification of query plan when converting outer join to inner join. Also relax the requirements of optimization to be able to apply it in cases when injective functions are applied to the aggregating keys during joins. [#92503](https://github.com/ClickHouse/ClickHouse/pull/92503) ([János Benjamin Antal](https://github.com/antaljanosbenjamin)).
- Fix possible error `SIZES_OF_COLUMNS_DOESNT_MATCH` during sorting of emty tuple column. Closes [#92422](https://github.com/ClickHouse/ClickHouse/issues/92422). [#92520](https://github.com/ClickHouse/ClickHouse/pull/92520) ([Pavel Kruglov](https://github.com/Avogar)).
- Check for incompatible typed paths in JSON type. Closes [#91577](https://github.com/ClickHouse/ClickHouse/issues/91577). [#92539](https://github.com/ClickHouse/ClickHouse/pull/92539) ([Pavel Kruglov](https://github.com/Avogar)).
- Fix deadlock for SHOW CREATE DATABASE for Backup database. [#92541](https://github.com/ClickHouse/ClickHouse/pull/92541) ([Azat Khuzhin](https://github.com/azat)).
- Use proper error code when validating hypothesis index. [#92559](https://github.com/ClickHouse/ClickHouse/pull/92559) ([Raúl Marín](https://github.com/Algunenano)).
- Fix dynamic subcolumns resolution in column aliases in analyzer. Previously dynamic subcolumn in column alias was wrapped in `getSubcolumn` and in some cases could be not resolved at all. Closes [#91434](https://github.com/ClickHouse/ClickHouse/issues/91434). [#92583](https://github.com/ClickHouse/ClickHouse/pull/92583) ([Pavel Kruglov](https://github.com/Avogar)).
- Prevent crash in tokens() with null second argument. [#92586](https://github.com/ClickHouse/ClickHouse/pull/92586) ([Raúl Marín](https://github.com/Algunenano)).
- Fix potential crash caused by in place mutation of underlying const PREWHERE columns. This could've happened at column shrinking (`IColumn::shrinkToFit`) or filtering (`IColumn::filter`), which could've triggered concurrently from several threads. [#92588](https://github.com/ClickHouse/ClickHouse/pull/92588) ([Arsen Muk](https://github.com/arsenmuk)).
- Creating and materializing text indexes on tables containing large parts (over 4,294,967,295 rows) is temporarily disabled. This limitation prevents incorrect query results, as the current index implementation does not yet support such large parts. [#92644](https://github.com/ClickHouse/ClickHouse/pull/92644) ([Anton Popov](https://github.com/CurtizJ)).
- Fixes a logical error `Too large size (A) passed to allocator` while executing JOINs. Closes [#92043](https://github.com/ClickHouse/ClickHouse/issues/92043). [#92667](https://github.com/ClickHouse/ClickHouse/pull/92667) ([Yarik Briukhovetskyi](https://github.com/yariks5s)).
- Remove a bug that `ngrambf_v1` indexes with ngram length (1st parameter) > 8 would throw an exception. [#92672](https://github.com/ClickHouse/ClickHouse/pull/92672) ([Robert Schulze](https://github.com/rschu1ze)).
- Fix uncaught exception during background named collections reload when zookeeper storage is used. Closes <https://github.com/ClickHouse/clickhouse-private/issues/44180>. [#92717](https://github.com/ClickHouse/ClickHouse/pull/92717) ([Kseniia Sumarokova](https://github.com/kssenii)).
- Reworks incorrect logic in access grant checks for wildcard grants. The previous attempt <https://github.com/ClickHouse/ClickHouse/pull/90928> addressed a critical vulnerability but ended up being too restrictive, resulting in some wildcard `GRANT` statements failing due to unrelated revokes. [#92725](https://github.com/ClickHouse/ClickHouse/pull/92725) ([pufit](https://github.com/pufit)).
- Fix bug in data skipping logic when `not match(...)` is used in `WHERE` causing incorrect results. Closes [#92492](https://github.com/ClickHouse/ClickHouse/issues/92492). [#92726](https://github.com/ClickHouse/ClickHouse/pull/92726) ([Nihal Z. Miaji](https://github.com/nihalzp)).
- Do not attempt to delete temporary directories at startup if a MergeTree table is created over a read-only disk. [#92748](https://github.com/ClickHouse/ClickHouse/pull/92748) ([Alexey Milovidov](https://github.com/alexey-milovidov)).
- Fix "Cannot add action to empty ExpressionActionsChain" for ALTER TABLE REWRITE PARTS (v2). [#92754](https://github.com/ClickHouse/ClickHouse/pull/92754) ([Azat Khuzhin](https://github.com/azat)).
- Avoid crash due to reading from a disconnected `Connection`. [#92807](https://github.com/ClickHouse/ClickHouse/pull/92807) ([Raufs Dunamalijevs](https://github.com/rienath)).
- Fix logical error  `Failed to set file processing within 100 retries` in storgae `S3Queue` in `Ordered` mode. It is now replaced with a warning. This error could happen before 25.10 version if keeper session expired, however it will still be a warning in 25.10+ versions, as it is still theoretically possible to get this error in case of high processing concurrency in `Ordered` mode. [#92814](https://github.com/ClickHouse/ClickHouse/pull/92814) ([Kseniia Sumarokova](https://github.com/kssenii)).
- Previously, some queries that used PK sharding with a false condition were failing. Now they're not. Needed for <https://github.com/ClickHouse/ClickHouse/pull/89313>. [#92815](https://github.com/ClickHouse/ClickHouse/pull/92815) ([Yarik Briukhovetskyi](https://github.com/yariks5s)).
- Fixed calculation of uncompressed sizes of text indexes in the `system.parts` table. [#92832](https://github.com/ClickHouse/ClickHouse/pull/92832) ([Anton Popov](https://github.com/CurtizJ)).
- Fixed usage of primary index in lightweight updates that have an `IN` clause with subqueries in the predicate of the `WHERE` clause. [#92838](https://github.com/ClickHouse/ClickHouse/pull/92838) ([Anton Popov](https://github.com/CurtizJ)).
- Fix creating type hint for path 'skip' in JSON. Closes [#92731](https://github.com/ClickHouse/ClickHouse/issues/92731). [#92842](https://github.com/ClickHouse/ClickHouse/pull/92842) ([Pavel Kruglov](https://github.com/Avogar)).
- In the S3 table engine, we should avoid caching the partition key if there are non-deterministic functions. [#92844](https://github.com/ClickHouse/ClickHouse/pull/92844) ([Miсhael Stetsyuk](https://github.com/mstetsyuk)).
- Fix possible error `FILE_DOESNT_EXIST` after mutation of a sparse column with `ratio_of_defaults_for_sparse_serialization=0.0`. Closes [#92633](https://github.com/ClickHouse/ClickHouse/issues/92633). [#92860](https://github.com/ClickHouse/ClickHouse/pull/92860) ([Pavel Kruglov](https://github.com/Avogar)).
- Fix parquet schema inference in the old parquet reader (not used by default) when a JSON column comes after a Tupe column. Fix the old parquet reader (not used by default) failing on empty tuples. [#92867](https://github.com/ClickHouse/ClickHouse/pull/92867) ([Michael Kolupaev](https://github.com/al13n321)).
- Fix logical error with multiple joins on constant condition and `join_use_nulls`, close [#92640](https://github.com/ClickHouse/ClickHouse/issues/92640). [#92892](https://github.com/ClickHouse/ClickHouse/pull/92892) ([Vladimir Cherkasov](https://github.com/vdimir)).
- Fix possible error `NOT_FOUND_COLUMN_IN_BLOCK` during insert into a table with subcolumn in partition expression. Closes [#93210](https://github.com/ClickHouse/ClickHouse/issues/93210). Closes [#83406](https://github.com/ClickHouse/ClickHouse/issues/83406). [#92905](https://github.com/ClickHouse/ClickHouse/pull/92905) ([Pavel Kruglov](https://github.com/Avogar)).
- Fix error `NO_SUCH_COLUMN_IN_TABLE` in Merge engine over tables with aliases. Closes [#88665](https://github.com/ClickHouse/ClickHouse/issues/88665). [#92910](https://github.com/ClickHouse/ClickHouse/pull/92910) ([Pavel Kruglov](https://github.com/Avogar)).