ClickHouse/docs/changelogs/v21.4.4.30-stable.md
2022-05-25 00:05:54 +02:00

4.8 KiB

ClickHouse release v21.4.4.30-stable FIXME as compared to v21.4.3.21-stable

Backward Incompatible Change

  • Backported in #23145: Now replicas that are processing the ALTER TABLE ATTACH PART[ITION] command search in their detached/ folders before fetching the data from other replicas. As an implementation detail, a new command ATTACH_PART is introduced in the replicated log. Parts are searched and compared by their checksums. #18978 (Mike Kot).

New Feature

  • Backported in #23147: Improved performance of dictGetHierarchy, dictIsIn functions. Added functions dictGetChildren(dictionary, key), dictGetDescendants(dictionary, key, level). Function dictGetChildren return all children as an array if indexes. It is a inverse transformation for dictGetHierarchy. Function dictGetDescendants return all descendants as if dictGetChildren was applied level times recursively. Zero level value is equivalent to infinity. Closes #14656. #22096 (Maksim Kita).
  • Backported in #23146: Added function dictGetOrNull. It works like dictGet, but return Null in case key was not found in dictionary. Closes #22375. #22413 (Maksim Kita).

Improvement

  • Backported in #23148: Add aliases simpleJSONExtract/simpleJSONHas to visitParam/visitParamExtract{UInt, Int, Bool, Float, Raw, String}. Fixes #21383. #21519 (fastio).
  • Backported in #23016: Set background_fetches_pool_size to 8 that is better for production usage with frequent small insertions or slow ZooKeeper cluster. #22945 (Alexey Milovidov).
  • Backported in #23079: Raised the threshold on max number of matches in result of the function extractAllGroupsHorizontal. #23036 (Vasily Nemkov).

Bug Fix

  • Backported in #23158: Fixed a bug with unlimited wait for auxiliary AWS requests. #22594 (Vladimir Chebotarev).
  • Backported in #23018: fixed formatDateTime() on DateTime64 and "%C" format specifier fixed toDateTime64() for large values and non-zero scale. ... #22937 (Vasily Nemkov).
  • Backported in #23031: Fix error Cannot find column in ActionsDAG result which may happen if subquery uses untuple. Fixes #22290. #22991 (Nikolai Kochetov).
  • Backported in #23074: Remove non-essential details from suggestions in clickhouse-client. This closes #22158. #23040 (Alexey Milovidov).
  • Backported in #23097: Fixed Table .inner_id... doesn't exist error when selecting from Materialized View after detaching it from Atomic database and attaching back. #23047 (Alexander Tokmakov).
  • Backported in #23173: Some values were formatted with alignment in center in table cells in Markdown format. Not anymore. #23096 (Alexey Milovidov).

Build/Testing/Packaging Improvement