### ClickHouse release v21.6.4.26-stable FIXME as compared to v21.6.3.14-stable
#### Bug Fix
* Backported in [#24969](https://github.com/ClickHouse/ClickHouse/issues/24969): Allow NULL values in postgresql protocol. Closes [#22622](https://github.com/ClickHouse/ClickHouse/issues/22622). [#24857](https://github.com/ClickHouse/ClickHouse/pull/24857) ([Kseniia Sumarokova](https://github.com/kssenii)).
* Backported in [#25186](https://github.com/ClickHouse/ClickHouse/issues/25186): Fixed bug with declaring S3 disk at root of bucket. Earlier, it reported an error: ``` [heather] 2021.05.10 02:11:11.932234 [ 72790 ] {2ff80b7b-ec53-41cb-ac35-19bb390e1759} <Error> executeQuery: Code: 36, e.displayText() = DB::Exception: Key name is empty in path style S3 URI: (http://172.17.0.2/bucket/) (version 21.6.1.1) (from 127.0.0.1:47994) (in query: SELECT policy_name FROM system.storage_policies), Stack trace (when copying this message, always include the lines below):. [#24898](https://github.com/ClickHouse/ClickHouse/pull/24898) ([Vladimir Chebotarev](https://github.com/excitoon)).
* Backported in [#25023](https://github.com/ClickHouse/ClickHouse/issues/25023): Fix limit/offset settings for distributed queries (ignore on the remote nodes). [#24940](https://github.com/ClickHouse/ClickHouse/pull/24940) ([Azat Khuzhin](https://github.com/azat)).
* Backported in [#25049](https://github.com/ClickHouse/ClickHouse/issues/25049): Fix extremely rare error `Tagging already tagged part` in replication queue during concurrent `alter move/replace partition`. Possibly fixes [#22142](https://github.com/ClickHouse/ClickHouse/issues/22142). [#24961](https://github.com/ClickHouse/ClickHouse/pull/24961) ([alesapin](https://github.com/alesapin)).
* Backported in [#25081](https://github.com/ClickHouse/ClickHouse/issues/25081): Fix wrong result when using aggregate projection with **not empty**`GROUP BY` key to execute query with `GROUP BY` by **empty** key. [#25055](https://github.com/ClickHouse/ClickHouse/pull/25055) ([Amos Bird](https://github.com/amosbird)).
* Backported in [#25107](https://github.com/ClickHouse/ClickHouse/issues/25107): Fix bug which allows creating tables with columns referencing themselves like `a UInt32 ALIAS a + 1` or `b UInt32 MATERIALIZED b`. Fixes [#24910](https://github.com/ClickHouse/ClickHouse/issues/24910), [#24292](https://github.com/ClickHouse/ClickHouse/issues/24292). [#25059](https://github.com/ClickHouse/ClickHouse/pull/25059) ([alesapin](https://github.com/alesapin)).
* Backported in [#25106](https://github.com/ClickHouse/ClickHouse/issues/25106): Fix bug with constant maps in mapContains that lead to error `empty column was returned by function mapContains`. Closes [#25077](https://github.com/ClickHouse/ClickHouse/issues/25077). [#25080](https://github.com/ClickHouse/ClickHouse/pull/25080) ([Kruglov Pavel](https://github.com/Avogar)).
* Backported in [#25143](https://github.com/ClickHouse/ClickHouse/issues/25143): Fix crash in query with cross join and `joined_subquery_requires_alias = 0`. Fixes [#24011](https://github.com/ClickHouse/ClickHouse/issues/24011). [#25082](https://github.com/ClickHouse/ClickHouse/pull/25082) ([Nikolai Kochetov](https://github.com/KochetovNicolai)).
* Backported in [#25157](https://github.com/ClickHouse/ClickHouse/issues/25157): Fix possible parts loss after updating up to 21.5 in case table used `UUID` in partition key. (It is not recommended to use `UUID` in partition key). Fixes [#25070](https://github.com/ClickHouse/ClickHouse/issues/25070). [#25127](https://github.com/ClickHouse/ClickHouse/pull/25127) ([Nikolai Kochetov](https://github.com/KochetovNicolai)).
* Backported in [#25182](https://github.com/ClickHouse/ClickHouse/issues/25182): Do not use table's projection for `SELECT` with `FINAL`. It is not supported yet. [#25163](https://github.com/ClickHouse/ClickHouse/pull/25163) ([Amos Bird](https://github.com/amosbird)).