title_wip

#### Improvement[​](#improvement-4 "Direct link to Improvement")

- Setting `allow_experimental_analyzer` is renamed to `enable_analyzer`. The old name is preserved in a form of an alias. This signifies that Analyzer is no longer in beta and is fully promoted to production. [#66438](https://github.com/ClickHouse/ClickHouse/pull/66438) ([Nikita Mikhaylov](https://github.com/nikitamikhaylov)).
- Improve schema inference of date times. Now DateTime64 used only when date time has fractional part, otherwise regular DateTime is used. Inference of Date/DateTime is more strict now, especially when `date_time_input_format='best_effort'` to avoid inferring date times from strings in corner cases. [#68382](https://github.com/ClickHouse/ClickHouse/pull/68382) ([Kruglov Pavel](https://github.com/Avogar)).
- ClickHouse server now supports new setting `max_keep_alive_requests`. For keep-alive HTTP connections to the server it works in tandem with `keep_alive_timeout` - if idle timeout not expired but there already more than `max_keep_alive_requests` requests done through the given connection - it will be closed by the server. [#61793](https://github.com/ClickHouse/ClickHouse/pull/61793) ([Nikita Taranov](https://github.com/nickitat)).
- Various improvements in the advanced dashboard. This closes [#67697](https://github.com/ClickHouse/ClickHouse/issues/67697). This closes [#63407](https://github.com/ClickHouse/ClickHouse/issues/63407). This closes [#51129](https://github.com/ClickHouse/ClickHouse/issues/51129). This closes [#61204](https://github.com/ClickHouse/ClickHouse/issues/61204). [#67701](https://github.com/ClickHouse/ClickHouse/pull/67701) ([Alexey Milovidov](https://github.com/alexey-milovidov)).
- Do not require a grant for REMOTE when creating a Distributed table: a grant for the Distributed engine is enough. [#65419](https://github.com/ClickHouse/ClickHouse/pull/65419) ([jsc0218](https://github.com/jsc0218)).
- Do not pass logs for keeper explicitly in the Docker image to allow overriding. [#65564](https://github.com/ClickHouse/ClickHouse/pull/65564) ([Azat Khuzhin](https://github.com/azat)).
- Introduced `use_same_password_for_base_backup` settings for `BACKUP` and `RESTORE` queries, allowing to create and restore incremental backups to/from password protected archives. [#66214](https://github.com/ClickHouse/ClickHouse/pull/66214) ([Samuele](https://github.com/sguerrini97)).
- Ignore `async_load_databases` for `ATTACH` query (previously it was possible for ATTACH to return before the tables had been attached). [#66240](https://github.com/ClickHouse/ClickHouse/pull/66240) ([Azat Khuzhin](https://github.com/azat)).
- Added logs and metrics for rejected connections (where there are not enough resources). [#66410](https://github.com/ClickHouse/ClickHouse/pull/66410) ([Alexander Tokmakov](https://github.com/tavplubix)).
- Support proper `UUID` type for MongoDB engine. [#66671](https://github.com/ClickHouse/ClickHouse/pull/66671) ([Azat Khuzhin](https://github.com/azat)).
- Add replication lag and recovery time metrics. [#66703](https://github.com/ClickHouse/ClickHouse/pull/66703) ([Miсhael Stetsyuk](https://github.com/mstetsyuk)).
- Add `DiskS3NoSuchKeyErrors` metric. [#66704](https://github.com/ClickHouse/ClickHouse/pull/66704) ([Miсhael Stetsyuk](https://github.com/mstetsyuk)).
- Ensure the `COMMENT` clause works for all table engines. [#66832](https://github.com/ClickHouse/ClickHouse/pull/66832) ([Joe Lynch](https://github.com/joelynch)).
- Function `mapFromArrays` now accepts `Map(K, V)` as first argument, for example: `SELECT mapFromArrays(map('a', 4, 'b', 4), ['aa', 'bb'])` now works and returns `{('a',4):'aa',('b',4):'bb'}`. Also, if the 1st argument is an Array, it can now also be of type `Array(Nullable(T))` or `Array(LowCardinality(Nullable(T)))` as long as the actual array values are not `NULL`. [#67103](https://github.com/ClickHouse/ClickHouse/pull/67103) ([李扬](https://github.com/taiyang-li)).
- Read configuration for `clickhouse-local` from `~/.clickhouse-local`. [#67135](https://github.com/ClickHouse/ClickHouse/pull/67135) ([Azat Khuzhin](https://github.com/azat)).
- Rename setting `input_format_orc_read_use_writer_time_zone` to `input_format_orc_reader_timezone` and allow the user to set the reader timezone. [#67175](https://github.com/ClickHouse/ClickHouse/pull/67175) ([kevinyhzou](https://github.com/KevinyhZou)).
- Decrease level of the `Socket is not connected` error when HTTP connection immediately reset by peer after connecting, close [#34218](https://github.com/ClickHouse/ClickHouse/issues/34218). [#67177](https://github.com/ClickHouse/ClickHouse/pull/67177) ([vdimir](https://github.com/vdimir)).
- Add ability to load dashboards for `system.dashboards` from config (once set, they overrides the default dashboards preset). [#67232](https://github.com/ClickHouse/ClickHouse/pull/67232) ([Azat Khuzhin](https://github.com/azat)).
- The window functions in SQL are traditionally in snake case. ClickHouse uses `camelCase`, so new aliases `denseRank()` and `percentRank()` have been created. These new functions can be called the exact same as the original `dense_rank()` and `percent_rank()` functions. Both snake case and camelCase syntaxes remain usable. A new test for each of the functions has been added as well. This closes [#67042](https://github.com/ClickHouse/ClickHouse/issues/67042) . [#67334](https://github.com/ClickHouse/ClickHouse/pull/67334) ([Peter Nguyen](https://github.com/petern48)).
- Autodetect configuration file format if is not `.xml`, `.yml` or `.yaml`. If the file begins with < it might be XML, otherwise it might be YAML. It is useful when providing a configuration file from a pipe: `clickhouse-server --config-file <(echo "hello: world")`. [#67391](https://github.com/ClickHouse/ClickHouse/pull/67391) ([sakulali](https://github.com/sakulali)).
- Functions `formatDateTime` and `formatDateTimeInJodaSyntax` now treat their format parameter as optional. If it is not specified, format strings `%Y-%m-%d %H:%i:%s` and `yyyy-MM-dd HH:mm:ss` are assumed. Example: `SELECT parseDateTime('2021-01-04 23:12:34')` now returns DateTime value `2021-01-04 23:12:34` (previously, this threw an exception). [#67399](https://github.com/ClickHouse/ClickHouse/pull/67399) ([Robert Schulze](https://github.com/rschu1ze)).
- Automatically retry Keeper requests in KeeperMap if they happen because of timeout or connection loss. [#67448](https://github.com/ClickHouse/ClickHouse/pull/67448) ([Antonio Andelic](https://github.com/antonio2368)).
- Add `-no-pie` to Aarch64 Linux builds to allow proper introspection and symbolizing of stacktraces after a ClickHouse restart. [#67916](https://github.com/ClickHouse/ClickHouse/pull/67916) ([filimonov](https://github.com/filimonov)).
- Added profile events for merges and mutations for better introspection. [#68015](https://github.com/ClickHouse/ClickHouse/pull/68015) ([Anton Popov](https://github.com/CurtizJ)).
- Remove unnecessary logs for non-replicated `MergeTree`. [#68238](https://github.com/ClickHouse/ClickHouse/pull/68238) ([Daniil Ivanik](https://github.com/divanik)).

#### Build/Testing/Packaging Improvement[​](#buildtestingpackaging-improvement-1 "Direct link to Build/Testing/Packaging Improvement")