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sidebar_label: 2022
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# 2022 Changelog

### ClickHouse release v21.2.7.11-stable FIXME as compared to v21.2.6.1-stable

#### Bug Fix
* Backported in [#21206](https://github.com/ClickHouse/ClickHouse/issues/21206): Fix the metadata leak when the Replicated*MergeTree with custom (non default) ZooKeeper cluster is dropped. [#21119](https://github.com/ClickHouse/ClickHouse/pull/21119) ([fastio](https://github.com/fastio)).
* Backported in [#21927](https://github.com/ClickHouse/ClickHouse/issues/21927): Fix Avro format parsing for Kafka. Fixes [#21437](https://github.com/ClickHouse/ClickHouse/issues/21437). [#21438](https://github.com/ClickHouse/ClickHouse/pull/21438) ([Ilya Golshtein](https://github.com/ilejn)).
* Backported in [#21855](https://github.com/ClickHouse/ClickHouse/issues/21855): Fix possible error ` Cannot find column` when `optimize_skip_unused_shards` is enabled and zero shards are used. [#21579](https://github.com/ClickHouse/ClickHouse/pull/21579) ([Azat Khuzhin](https://github.com/azat)).
* Backported in [#21688](https://github.com/ClickHouse/ClickHouse/issues/21688): Fix fsync_part_directory for horizontal merge. [#21642](https://github.com/ClickHouse/ClickHouse/pull/21642) ([Azat Khuzhin](https://github.com/azat)).
* Backported in [#21795](https://github.com/ClickHouse/ClickHouse/issues/21795): Fix distributed requests cancellation (for example simple select from multiple shards with limit, i.e. `select * from remote('127.{2,3}', system.numbers) limit 100`) with `async_socket_for_remote=1`. [#21643](https://github.com/ClickHouse/ClickHouse/pull/21643) ([Azat Khuzhin](https://github.com/azat)).
* Backported in [#21879](https://github.com/ClickHouse/ClickHouse/issues/21879): Fix possible crashes in aggregate functions with combinator Distinct, while using two-level aggregation. This is a follow-up fix of https://github.com/ClickHouse/ClickHouse/pull/18365 . Can only reproduced in production env. No test case available yet. cc @CurtizJ. [#21818](https://github.com/ClickHouse/ClickHouse/pull/21818) ([Amos Bird](https://github.com/amosbird)).
* Backported in [#21979](https://github.com/ClickHouse/ClickHouse/issues/21979): Reverted [#15454](https://github.com/ClickHouse/ClickHouse/issues/15454) that may cause significant increase in memory usage while loading external dictionaries of hashed type. This closes [#21935](https://github.com/ClickHouse/ClickHouse/issues/21935). [#21948](https://github.com/ClickHouse/ClickHouse/pull/21948) ([Maksim Kita](https://github.com/kitaisreal)).
* Backported in [#22140](https://github.com/ClickHouse/ClickHouse/issues/22140): The function `decrypt` was lacking a check for the minimal size of data encrypted in AEAD mode. This closes [#21897](https://github.com/ClickHouse/ClickHouse/issues/21897). [#22064](https://github.com/ClickHouse/ClickHouse/pull/22064) ([Alexey Milovidov](https://github.com/alexey-milovidov)).

#### NOT FOR CHANGELOG / INSIGNIFICANT

* LRUCache fix exception unsafe element insertion [#21891](https://github.com/ClickHouse/ClickHouse/pull/21891) ([Maksim Kita](https://github.com/kitaisreal)).
