v25.12 Changelog for Cloud

### Iceberg and data lakes[​](#iceberg-and-data-lakes "Direct link to Iceberg and data lakes")

- Support `ORDER BY` in `CREATE` operation for iceberg + sorting in `INSERT`. Resolves [#89916](https://github.com/ClickHouse/ClickHouse/issues/89916). [#90141](https://github.com/ClickHouse/ClickHouse/pull/90141) ([Konstantin Vedernikov](https://github.com/scanhex12)).

### SQL and query features[​](#sql-and-query-features "Direct link to SQL and query features")

- Add `allow_reentry` option to `windowFunnel` aggregate function. When enabled with strict\_order, it ignores events that violate the order instead of stopping the funnel analysis. This enables handling user journeys with refreshes (A->A->B) or back-navigation (A->B->A->C) without underreporting conversion rates. [#86916](https://github.com/ClickHouse/ClickHouse/pull/86916) ([Lee ChaeRok](https://github.com/LeeChaeRok)).
- User can now add a new argument `preprocessor` in text index construction. The argument is an arbitrary expression that transforms each document before tokenization. [#88272](https://github.com/ClickHouse/ClickHouse/pull/88272) ([Jimmy Aguilar Mena](https://github.com/Ergus)).
- Add support for fractional `LIMIT` and `OFFSET` for selecting a fraction of a table. Closes [#81892](https://github.com/ClickHouse/ClickHouse/issues/81892). [#88755](https://github.com/ClickHouse/ClickHouse/pull/88755) ([Ahmed Gouda](https://github.com/0xgouda)).
- Add setting into\_outfile\_create\_parent\_directories to automatically create parent directories for INTO OUTFILE, preventing errors when output paths do not exist. Resolves [#88610](https://github.com/ClickHouse/ClickHouse/issues/88610). [#88795](https://github.com/ClickHouse/ClickHouse/pull/88795) ([Saksham](https://github.com/Saksham10-11)).
- Add setting `type_json_skip_invalid_typed_paths` to disable exceptions for inserts/type casts to JSON type when input JSON cannot be cast to explicit typed paths in JSON type. Falls back to null/zero value of typed path. Closes [#86917](https://github.com/ClickHouse/ClickHouse/issues/86917). [#89886](https://github.com/ClickHouse/ClickHouse/pull/89886) ([Max Justus Spransy](https://github.com/maxjustus)).

### Client and CLI features[​](#client-and-cli-features "Direct link to Client and CLI features")

- CLI client can now suppress the 'ClickHouse server version is older than ClickHouse client. It may indicate that the server is out of date and can be upgraded.' message by specifying `--no-server-client-version-message` or `false`. [#87784](https://github.com/ClickHouse/ClickHouse/pull/87784) ([Larry Snizek](https://github.com/larry-cdn77)).
- Access ClickHouse Cloud instances using Cloud credentials with --login. [#89261](https://github.com/ClickHouse/ClickHouse/pull/89261) ([Krishna Mannem](https://github.com/kcmannem)).
- Web UI now provides a download button. It downloads the full result even if the UI displays only part of it. [#89768](https://github.com/ClickHouse/ClickHouse/pull/89768) ([Alexey Milovidov](https://github.com/alexey-milovidov)).

### Server configuration and monitoring[​](#server-configuration-and-monitoring "Direct link to Server configuration and monitoring")

- Adds a `memory_usage` field to `X-ClickHouse-Progress` and `X-ClickHouse-Summary`. This can be used to collect memory usage of queries in real time on the client side. [#88393](https://github.com/ClickHouse/ClickHouse/pull/88393) ([Christoph Wurm](https://github.com/cwurm)).
- Added `send_profile_events` setting which allows clients to reduce network traffic when profile events are unused. [#89588](https://github.com/ClickHouse/ClickHouse/pull/89588) ([Kaviraj Kanagaraj](https://github.com/kavirajk)).

### Keeper[​](#keeper "Direct link to Keeper")

- Keeper compatibility with zookeeper: create with statistics. [#88797](https://github.com/ClickHouse/ClickHouse/pull/88797) ([Konstantin Vedernikov](https://github.com/scanhex12)).
- Support for ZooKeeper persistent watches in ClickHouse Keeper. [#88813](https://github.com/ClickHouse/ClickHouse/pull/88813) ([Konstantin Vedernikov](https://github.com/scanhex12)).

### Input/Output formats[​](#input-output-formats "Direct link to Input/Output formats")

- Implement new input output format `Buffers`. This format is similar to `Native`; however, unlike `Native`, it does not store column names, column types, or any extra metadata. Closes [#84017](https://github.com/ClickHouse/ClickHouse/issues/84017). [#91156](https://github.com/ClickHouse/ClickHouse/pull/91156) ([Nihal Z. Miaji](https://github.com/nihalzp)).
- Add `arrow_flight_request_descriptor_type` setting to support Dremio and other Arrow Flight servers that require command-style descriptors. Fixes [#89523](https://github.com/ClickHouse/ClickHouse/issues/89523). [#89826](https://github.com/ClickHouse/ClickHouse/pull/89826) ([Shreyas Ganesh](https://github.com/shreyasganesh0)).
- Added `kafka_schema_registry_skip_bytes` setting to Kafka table engine to skip envelope header bytes (e.g., AWS Glue Schema Registry's 19-byte prefix) before parsing message payload. [#89621](https://github.com/ClickHouse/ClickHouse/pull/89621) ([Taras Polishchuk](https://github.com/wake-up-neo)).

### Other new features[​](#other-new-features "Direct link to Other new features")

- Add a setting `max_streams_for_files_processing_in_cluster_functions` to control number of streams for parallel files reading in Cluster table functions. Closes [#90223](https://github.com/ClickHouse/ClickHouse/issues/90223). [#91323](https://github.com/ClickHouse/ClickHouse/pull/91323) ([Pavel Kruglov](https://github.com/Avogar)).
- Allow disabling background download of nearby part data on a per-query basis. Fixes [#89524](https://github.com/ClickHouse/ClickHouse/issues/89524). [#89668](https://github.com/ClickHouse/ClickHouse/pull/89668) ([tanner-bruce](https://github.com/tanner-bruce)).
- Experimentally support e2k (Elbrus-2000) as a new platform for ClickHouse. [#90159](https://github.com/ClickHouse/ClickHouse/pull/90159) ([Ramil Sattarov](https://github.com/r-a-sattarov)).

## Experimental Features[​](#experimental-features "Direct link to Experimental Features")

- Support TLS certificates retrieval from ACME providers, [RFC 8555](https://datatracker.ietf.org/doc/html/rfc8555). [#66315](https://github.com/ClickHouse/ClickHouse/pull/66315) ([Konstantin Bogdanov](https://github.com/thevar1able)).
- The new logic is introduced to automatically execute queries using parallel replicas, controlled by the setting `automatic_parallel_replicas_mode`. [#87541](https://github.com/ClickHouse/ClickHouse/pull/87541) ([Nikita Taranov](https://github.com/nickitat)).
- Full-text search is now in private preview (from a previously experimental stage). [#88928](https://github.com/ClickHouse/ClickHouse/pull/88928) ([Robert Schulze](https://github.com/rschu1ze)).
- Move `Alias` to experimental, can be enabled with `allow_experimental_alias_table_engine=1`. [#89712](https://github.com/ClickHouse/ClickHouse/pull/89712) ([Kai Zhu](https://github.com/nauu)).

## Performance Improvements[​](#performance-improvements "Direct link to Performance Improvements")

### Query execution and optimization[​](#query-execution-and-optimization "Direct link to Query execution and optimization")