v25.4 Changelog for Cloud

- Support using a remote disk for databases to store metadata files. [#77365](https://github.com/ClickHouse/ClickHouse/pull/77365) ([Tuan Pham Anh](https://github.com/tuanpach)).
- Implement comparison for values of JSON data type. Now JSON objects can be compared similarly to Maps. [#77397](https://github.com/ClickHouse/ClickHouse/pull/77397) ([Pavel Kruglov](https://github.com/Avogar)).
- Change reverted. [#77399](https://github.com/ClickHouse/ClickHouse/pull/77399) ([Yarik Briukhovetskyi](https://github.com/yariks5s)).
- Backup/restore setting `allow_s3_native_copy` now supports value three possible values: - `False` - s3 native copy will not be used; - `True` (old default) - ClickHouse will try s3 native copy first, if it fails then fallback to the reading+writing approach; - `'auto'` (new default) - ClickHouse will compare the source and destination credentials first. If they are same, ClickHouse will try s3 native copy and then may fallback to the reading+writing approach. If they are different, ClickHouse will go directly to the reading+writing approach. [#77401](https://github.com/ClickHouse/ClickHouse/pull/77401) ([Vitaly Baranov](https://github.com/vitlibar)).
- Support ALTER TABLE ... ATTACH|DETACH|MOVE|REPLACE PARTITION for the plain\_rewritable disk. [#77406](https://github.com/ClickHouse/ClickHouse/pull/77406) ([Julia Kartseva](https://github.com/jkartseva)).
- Skipping index cache is reverted. [#77447](https://github.com/ClickHouse/ClickHouse/pull/77447) ([Nikita Mikhaylov](https://github.com/nikitamikhaylov)).
- Reduce memory usage during prefetches of JSON column in Wide parts. [#77640](https://github.com/ClickHouse/ClickHouse/pull/77640) ([Pavel Kruglov](https://github.com/Avogar)).
- Support aws session token and environment credentials usage in delta kernel for DeltaLake table engine. [#77661](https://github.com/ClickHouse/ClickHouse/pull/77661) ([Kseniia Sumarokova](https://github.com/kssenii)).
- Support query parameters inside `additional_table_filters` setting. After the change, the following query would succeed:. [#77680](https://github.com/ClickHouse/ClickHouse/pull/77680) ([wxybear](https://github.com/wxybear)).
- User-defined functions (UDFs) can now be marked as deterministic via a new tag in their XML definition. Also, the query cache now checks if UDFs called within a query are deterministic. If this is the case, it caches the query result. (Issue [#59988](https://github.com/ClickHouse/ClickHouse/issues/59988)). [#77769](https://github.com/ClickHouse/ClickHouse/pull/77769) ([Jimmy Aguilar Mena](https://github.com/Ergus)).
- Added Buffer table engine parameters validation. [#77840](https://github.com/ClickHouse/ClickHouse/pull/77840) ([Pervakov Grigorii](https://github.com/GrigoryPervakov)).
- Add config `enable_hdfs_pread` to enable or disable hdfs pread. [#77885](https://github.com/ClickHouse/ClickHouse/pull/77885) ([kevinyhzou](https://github.com/KevinyhZou)).
- Add profile events for number of zookeeper 'multi' read and write requests. [#77888](https://github.com/ClickHouse/ClickHouse/pull/77888) ([JackyWoo](https://github.com/JackyWoo)).
- Allow creating and inserting into temp table when disable\_insertion\_and\_mutation is on. [#77901](https://github.com/ClickHouse/ClickHouse/pull/77901) ([Xu Jia](https://github.com/XuJia0210)).
- Decrease max\_insert\_delayed\_streams\_for\_parallel\_write (to 100). [#77919](https://github.com/ClickHouse/ClickHouse/pull/77919) ([Azat Khuzhin](https://github.com/azat)).
- Add ability to configure number of columns that merges can flush in parallel using `max_merge_delayed_streams_for_parallel_write` (this should reduce memory usage for vertical merges to S3 about 25x times). [#77922](https://github.com/ClickHouse/ClickHouse/pull/77922) ([Azat Khuzhin](https://github.com/azat)).
- Fix year parsing in joda syntax like 'yyy'. [#77973](https://github.com/ClickHouse/ClickHouse/pull/77973) ([李扬](https://github.com/taiyang-li)).
- Attaching parts of MergeTree tables will be performed in their block order, which is important for special merging algorithms, such as ReplacingMergeTree. This closes [#71009](https://github.com/ClickHouse/ClickHouse/issues/71009). [#77976](https://github.com/ClickHouse/ClickHouse/pull/77976) ([Alexey Milovidov](https://github.com/alexey-milovidov)).
- Query masking rules are now able to throw a LOGICAL\_ERROR in case if the match happened. This will help to check if pre-defined password is leaking anywhere in logs. [#78094](https://github.com/ClickHouse/ClickHouse/pull/78094) ([Nikita Mikhaylov](https://github.com/nikitamikhaylov)).
- Added column `index_length_column` to `information_schema.tables` for better compatibility with MySQL. [#78119](https://github.com/ClickHouse/ClickHouse/pull/78119) ([Paweł Zakrzewski](https://github.com/KrzaQ)).
- Introduce two new metrics: `TotalMergeFailures` and `NonAbortedMergeFailures`. These metrics are needed to detect the cases where too many merges fail within a short period. [#78150](https://github.com/ClickHouse/ClickHouse/pull/78150) ([Miсhael Stetsyuk](https://github.com/mstetsyuk)).
- Fix incorrect S3 uri parsing when key is not specified on path style. [#78185](https://github.com/ClickHouse/ClickHouse/pull/78185) ([Arthur Passos](https://github.com/arthurpassos)).
- Fix incorrect values of `BlockActiveTime`, `BlockDiscardTime`, `BlockWriteTime`, `BlockQueueTime`, and `BlockReadTime` asynchronous metrics (before the change 1 second was incorrectly reported as 0.001). [#78211](https://github.com/ClickHouse/ClickHouse/pull/78211) ([filimonov](https://github.com/filimonov)).
- Respect `loading_retries` limit for errors during push to materialized view for StorageS3(Azure)Queue. Before that such errors were retried indefinitely. [#78313](https://github.com/ClickHouse/ClickHouse/pull/78313) ([Kseniia Sumarokova](https://github.com/kssenii)).
- In StorageDeltaLake with delta-kernel-rs implementation, fix performance and progress bar. [#78368](https://github.com/ClickHouse/ClickHouse/pull/78368) ([Kseniia Sumarokova](https://github.com/kssenii)).
- Vector similarity index could over-allocate main memory by up to 2x. This fix reworks the memory allocation strategy, reducing the memory consumption and improving the effectiveness of the vector similarity index cache. (issue [#78056](https://github.com/ClickHouse/ClickHouse/issues/78056)). [#78394](https://github.com/ClickHouse/ClickHouse/pull/78394) ([Shankar Iyer](https://github.com/shankar-iyer)).
- Introduce a setting `schema_type` for `system.metric_log` table with schema type. There are three allowed schemas: `wide` -- current schema, each metric/event in a separate column (most effective for reads of separate columns), `transposed` -- similar to `system.asynchronous_metric_log`, metrics/events are stored as rows, and the most interesting `transposed_with_wide_view` -- create underlying table with `transposed` schema, but also introduce a view with `wide` schema which translates queries to underlying table. In `transposed_with_wide_view` subsecond resolution for view is not supported, `event_time_microseconds` is just an alias for backward compatibility. [#78412](https://github.com/ClickHouse/ClickHouse/pull/78412) ([alesapin](https://github.com/alesapin)).
- Support `include`, `from_env`, `from_zk` for runtime disks. Closes [#78177](https://github.com/ClickHouse/ClickHouse/issues/78177). [#78470](https://github.com/ClickHouse/ClickHouse/pull/78470) ([Kseniia Sumarokova](https://github.com/kssenii)).
- Add several convenient ways to resolve root metadata.json file in an iceberg table function and engine. Closes [#78455](https://github.com/ClickHouse/ClickHouse/issues/78455). [#78475](https://github.com/ClickHouse/ClickHouse/pull/78475) ([Daniil Ivanik](https://github.com/divanik)).
- Support partition pruning in delta lake. [#78486](https://github.com/ClickHouse/ClickHouse/pull/78486) ([Kseniia Sumarokova](https://github.com/kssenii)).
- Support password based auth in SSH protocol in ClickHouse. [#78586](https://github.com/ClickHouse/ClickHouse/pull/78586) ([Nikita Mikhaylov](https://github.com/nikitamikhaylov)).