ClickHouse/docs/changelogs/v21.1.8.30-stable.md

ClickHouse release v21.1.8.30-stable FIXME as compared to v21.1.7.1-stable

Bug Fix

• Backported in #21205: Fix the metadata leak when the Replicated*MergeTree with custom (non default) ZooKeeper cluster is dropped. #21119 (fastio).
• Backported in #21161: Fix input_format_null_as_default take effective when types are nullable. This fixes #21116 . #21121 (Amos Bird).
• Backported in #21926: Fix Avro format parsing for Kafka. Fixes #21437. #21438 (Ilya Golshtein).
• Backported in #22189: Fixed race on SSL object inside SecureSocket in Poco. #21456 (Nikita Mikhaylov).
• Backported in #22317: Remove unknown columns from joined table in where for queries to external database engines (MySQL, PostgreSQL). close #14614, close #19288 (dup), close #19645 (dup). #21640 (Vladimir C).
• Backported in #21797: 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 (Azat Khuzhin).
• Backported in #22287: Start accepting connections after DDLWorker and dictionaries initialization. #21676 (Azat Khuzhin).
• Backported in #21810: Fix bug for ReplicatedMerge table engines when ALTER MODIFY COLUMN query doesn't change the type of decimal column if its size (32 bit or 64 bit) doesn't change. #21728 (alesapin).
• Backported in #21880: 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 (Amos Bird).
• Backported in #22052: Fix deadlock in first catboost model execution. Closes #13832. #21844 (Kruglov Pavel).
• Backported in #21981: Reverted #15454 that may cause significant increase in memory usage while loading external dictionaries of hashed type. This closes #21935. #21948 (Maksim Kita).
• Backported in #22465: In rare case, merge for CollapsingMergeTree may create granule with index_granularity + 1 rows. Because of this, internal check, added in #18928 (affects 21.2 and 21.3), may fail with error Incomplete granules are not allowed while blocks are granules size. This error did not allow parts to merge. #21976 (Nikolai Kochetov).
• Backported in #22149: The function decrypt was lacking a check for the minimal size of data encrypted in AEAD mode. This closes #21897. #22064 (Alexey Milovidov).
• Backported in #22283: Docker entrypoint: avoid chown of . in case when LOG_PATH is empty. Closes #22100. #22102 (filimonov).
• Backported in #22280: Fix waiting for OPTIMIZE and ALTER queries for ReplicatedMergeTree table engines. Now the query will not hang when the table was detached or restarted. #22118 (alesapin).
• Backported in #22501: Fix query cancellation with use_hedged_requests=0 and async_socket_for_remote=1. #22183 (Azat Khuzhin).
• Backported in #22368: Now clickhouse will not throw LOGICAL_ERROR exception when we try to mutate the already covered part. Fixes #22013. #22291 (alesapin).
• Backported in #22533: Buffer overflow (on read) was possible in tokenbf_v1 full text index. The excessive bytes are not used but the read operation may lead to crash in rare cases. This closes #19233. #22421 (Alexey Milovidov).
• Backported in #22462: Add (missing) memory accounting in parallel parsing routines. In previous versions OOM was possible when the resultset contains very large blocks of data. This closes #22008. #22425 (Alexey Milovidov).
• Backported in #22555: Fix bug in partial merge join with LowCardinality. Close #22386, close #22388. #22510 (Vladimir C).
• Backported in #22608: Fix deserialization of empty string without newline at end of TSV format. This closes #20244. Possible workaround without version update: set input_format_null_as_default to zero. It was zero in old versions. #22527 (Alexey Milovidov).
• Backported in #22578: Fix UB by unlocking the rwlock of the TinyLog from the same thread. #22560 (Azat Khuzhin).
• Backported in #22650: Avoid UB in *Log engines for rwlock unlock due to unlock from another thread. #22583 (Azat Khuzhin).
• Backported in #22700: Fix wait for mutations on several replicas for ReplicatedMergeTree table engines. Previously, mutation/alter query may finish before mutation actually executed on other replicas. #22669 (alesapin).
• Backported in #22739: Fix possible hangs in zk requests in case of OOM exception. Fixes #22438. #22684 (Nikolai Kochetov).