v25.8 Changelog for Cloud

### Vector similarity index[​](#vector-similarity-index "Direct link to Vector similarity index")

- Prevent user from using `nan` and `inf` with `NumericIndexedVector`. Fixes [#82239](https://github.com/ClickHouse/ClickHouse/issues/82239) and a little more. [#82681](https://github.com/ClickHouse/ClickHouse/pull/82681) ([Raufs Dunamalijevs](https://github.com/rienath)).
- The vector similarity index now supports binary quantization. Binary quantization significantly reduces the memory consumption and speeds up the process of building a vector index (due to faster distance calculation). Also, the existing setting `vector_search_postfilter_multiplier` was made obsolete and replaced by a more general setting : `vector_search_index_fetch_multiplier`. [#85024](https://github.com/ClickHouse/ClickHouse/pull/85024) ([Shankar Iyer](https://github.com/shankar-iyer)).
- Approximate vector search with vector similarity indexes is now GA. [#85888](https://github.com/ClickHouse/ClickHouse/pull/85888) ([Robert Schulze](https://github.com/rschu1ze)).

### Error handling and messages[​](#error-handling-and-messages "Direct link to Error handling and messages")

- Header Connection is sent at the end of headers. When we know is the connection should be preserved. [#81951](https://github.com/ClickHouse/ClickHouse/pull/81951) ([Sema Checherinda](https://github.com/CheSema)).
- In previous versions, multiplication of the aggregate function state with IPv4 produced a logical error instead of a proper error code. Closes [#82817](https://github.com/ClickHouse/ClickHouse/issues/82817). [#82818](https://github.com/ClickHouse/ClickHouse/pull/82818) ([Alexey Milovidov](https://github.com/alexey-milovidov)).
- Better error handling in `AsynchronousMetrics`. If the `/sys/block` directory exists but is not accessible, the server will start without monitoring the block devices. Closes [#79229](https://github.com/ClickHouse/ClickHouse/issues/79229). [#83115](https://github.com/ClickHouse/ClickHouse/pull/83115) ([Alexey Milovidov](https://github.com/alexey-milovidov)).
- There was an incorrect dependency check for the `INSERT` with materialized views that have malformed selects and the user might have received an obscure `std::exception` instead of a meaningful error with a clear explanation. This is now fixed. This fixes: [#82889](https://github.com/ClickHouse/ClickHouse/issues/82889). [#83190](https://github.com/ClickHouse/ClickHouse/pull/83190) ([Nikita Mikhaylov](https://github.com/nikitamikhaylov)).
- Do not output very long descriptions of expression actions in exception messages. Closes [#83164](https://github.com/ClickHouse/ClickHouse/issues/83164). [#83350](https://github.com/ClickHouse/ClickHouse/pull/83350) ([Alexey Milovidov](https://github.com/alexey-milovidov)).
- When the storage is shutting down, `getStatus` throws an `ErrorCodes::ABORTED` exception. Previously, this would fail the select query. Now we catch the `ErrorCodes::ABORTED` exceptions and intentionally ignore them instead. [#83435](https://github.com/ClickHouse/ClickHouse/pull/83435) ([Miсhael Stetsyuk](https://github.com/mstetsyuk)).
- Make exception messages for certain situations for loading and adding projections easier to read. [#83728](https://github.com/ClickHouse/ClickHouse/pull/83728) ([Robert Schulze](https://github.com/rschu1ze)).
- Check if connection is cancelled before checking for EOF to prevent reading from closed connection. Fixes [#83893](https://github.com/ClickHouse/ClickHouse/issues/83893). [#84227](https://github.com/ClickHouse/ClickHouse/pull/84227) ([Raufs Dunamalijevs](https://github.com/rienath)).
- Improved server shutdown handling for client connections by simplifying internal checks. [#84312](https://github.com/ClickHouse/ClickHouse/pull/84312) ([Raufs Dunamalijevs](https://github.com/rienath)).
- Low-level errors during UDF execution now fail with error code `UDF_EXECUTION_FAILED`, whereas previously different error codes could be returned. [#84547](https://github.com/ClickHouse/ClickHouse/pull/84547) ([Xu Jia](https://github.com/XuJia0210)).

### SQL formatting improvements[​](#sql-formatting-improvements "Direct link to SQL formatting improvements")

- Fix inconsistent formatting of `CREATE DICTIONARY`. Closes [#82105](https://github.com/ClickHouse/ClickHouse/issues/82105). [#82829](https://github.com/ClickHouse/ClickHouse/pull/82829) ([Alexey Milovidov](https://github.com/alexey-milovidov)).
- Fix inconsistent formatting of `TTL` when it contains a `materialize` function. Closes [#82828](https://github.com/ClickHouse/ClickHouse/issues/82828). [#82831](https://github.com/ClickHouse/ClickHouse/pull/82831) ([Alexey Milovidov](https://github.com/alexey-milovidov)).
- Fix inconsistent formatting of `EXPLAIN AST` in a subquery when it contains output options such as INTO OUTFILE. Closes [#82826](https://github.com/ClickHouse/ClickHouse/issues/82826). [#82840](https://github.com/ClickHouse/ClickHouse/pull/82840) ([Alexey Milovidov](https://github.com/alexey-milovidov)).
- Fix inconsistent formatting of parenthesized expressions with aliases in the context when no aliases are allowed. Closes [#82836](https://github.com/ClickHouse/ClickHouse/issues/82836). Closes [#82837](https://github.com/ClickHouse/ClickHouse/issues/82837). [#82867](https://github.com/ClickHouse/ClickHouse/pull/82867) ([Alexey Milovidov](https://github.com/alexey-milovidov)).
- Fix formatting of CREATE USER with query parameters (i.e. `CREATE USER {username:Identifier} IDENTIFIED WITH no_password`). [#84376](https://github.com/ClickHouse/ClickHouse/pull/84376) ([Azat Khuzhin](https://github.com/azat)).
- Fix parsing of a trailing comma in columns of the CREATE DICTIONARY query after a column with parameters, for example, Decimal(8). Closes [#85586](https://github.com/ClickHouse/ClickHouse/issues/85586). [#85653](https://github.com/ClickHouse/ClickHouse/pull/85653) ([Nikolay Degterinsky](https://github.com/evillique)).

### External integrations[​](#external-integrations "Direct link to External integrations")

- Unify parameter names in ODBC and JDBC when using named collections. [#83410](https://github.com/ClickHouse/ClickHouse/pull/83410) ([Andrey Zvonov](https://github.com/zvonand)).
- MongoDB: Implicit parsing of strings to numeric types. Previously, if a string value was received from a MongoDB source for a numeric column in a ClickHouse table, an exception was thrown. Now, the engine attempts to parse the numeric value from the string automatically. Closes [#81167](https://github.com/ClickHouse/ClickHouse/issues/81167). [#84069](https://github.com/ClickHouse/ClickHouse/pull/84069) ([Kirill Nikiforov](https://github.com/allmazz)).
- Allow `simdjson` on unsupported architectures (previously leads to `CANNOT_ALLOCATE_MEMORY` errors). [#84966](https://github.com/ClickHouse/ClickHouse/pull/84966) ([Azat Khuzhin](https://github.com/azat)).

### Miscellaneous improvements[​](#miscellaneous-improvements "Direct link to Miscellaneous improvements")