ClickHouse/docs/changelogs/v21.7.2.7-stable.md

ClickHouse release v21.7.2.7-stable FIXME as compared to v21.7.1.7283-prestable

Improvement

• Backported in #25881: Allow to start clickhouse-client with unreadable working directory. #25817 (ianton-ru).

Bug Fix

• Backported in #25833: CAST from Date to DateTime (or DateTime64) was not using the timezone of the DateTime type. It can also affect the comparison between Date and DateTime. Inference of the common type for Date and DateTime also was not using the corresponding timezone. It affected the results of function if and array construction. Closes #24128. #24129 (Maksim Kita).
• Backported in #25766: Fix assertion in PREWHERE with non-uint8 type, close #19589. #25484 (Vladimir C).
• Backported in #25954: Fix ALTER MODIFY COLUMN of columns, which participates in TTL expressions. #25554 (Anton Popov).
• Backported in #25871: Fix rare bug with DROP PART query for ReplicatedMergeTree tables which can lead to error message Unexpected merged part intersecting drop range. #25783 (alesapin).
• Backported in #25886: Fix ARM exception handling with non default page size. Fixes #25512. Fixes #25044. Fixes #24901. Fixes #23183. Fixes #20221. Fixes #19703. Fixes #19028. Fixes #18391. Fixes #18121. Fixes #17994. Fixes #12483. #25854 (Maksim Kita).
• Backported in #25957: Fix extremely long backoff for background tasks when the background pool is full. Fixes #25836. #25893 (alesapin).
• Backported in #25932: Fix crash on call dictGet() with bad arguments. #25913 (Vitaly Baranov).
• Backported in #25981: Fix possible deadlock during query profiler stack unwinding. Fixes #25968. #25970 (Maksim Kita).
• Backported in #26010: Fix formatting of type Map with integer keys to JSON. #25982 (Anton Popov).
• Backported in #26097: Fix wrong thread estimation for right subquery join in some cases. Close #24075. #26052 (Vladimir C).