ClickHouse/docs/changelogs/v20.8.19.4-stable.md

ClickHouse release v20.8.19.4-stable FIXME as compared to v20.8.18.32-lts

Improvement

• Backported in #24720: If tuple of NULLs, e.g. (NULL, NULL) is on the left hand side of IN operator with tuples of non-NULLs on the right hand side, e.g. SELECT (NULL, NULL) IN ((0, 0), (3, 1)) return 0 instead of throwing an exception about incompatible types. The expression may also appear due to optimization of something like SELECT (NULL, NULL) = (8, 0) OR (NULL, NULL) = (3, 2) OR (NULL, NULL) = (0, 0) OR (NULL, NULL) = (3, 1). This closes #22017. #22063 (Alexey Milovidov).

Bug Fix

• Backported in #24713: Fixed very rare race condition on background cleanup of old blocks. It might cause a block not to be deduplicated if it's too close to the end of deduplication window. #23301 (Alexander Tokmakov).
• Backported in #24715: Fixed Cannot unlink file error on unsuccessful creation of ReplicatedMergeTree table with multidisk configuration. This closes #21755. #23433 (Alexander Tokmakov).
• Backported in #24717: When modify column's default value without datatype, and this column is used as ReplacingMergeTree's parameter like column b in the below example, then the server will core dump: CREATE TABLE alter_test (a Int32, b DateTime) ENGINE = ReplacingMergeTree(b) ORDER BY a; ALTER TABLE alter_test MODIFY COLUMN `b` DEFAULT now(); the sever throw error: 2021.04.22 09:48:00.685317 [ 2607 ] {} <Trace> BaseDaemon: Received signal 11 2021.04.22 09:48:00.686110 [ 2705 ] {} <Fatal> BaseDaemon: ######################################## 2021.04.22 09:48:00.686336 [ 2705 ] {} <Fatal> BaseDaemon: (version 21.6.1.1, build id: 6459E84DFCF8E778546C5AD2FFE91B3AD71E1B1B) (from thread 2619) (no query) Received signal Segmentation fault (11) 2021.04.22 09:48:00.686572 [ 2705 ] {} <Fatal> BaseDaemon: Address: NULL pointer. Access: read. Address not mapped to object. 2021.04.22 09:48:00.686686 [ 2705 ] {} <Fatal> BaseDaemon: Stack trace: 0x1c2585d7 0x1c254f66 0x1bb7e403 0x1bb58923 0x1bb56a85 0x1c6840ef 0x1c691148 0x2061a05c 0x2061a8e4 0x20775a03 0x207722bd 0x20771048 0x7f6e5c25be25 0x7f6e5bd81bad 2021.04.22 09:48:02.283045 [ 2705 ] {} <Fatal> BaseDaemon: 4. /mnt/disk4/hewenting/ClickHouse/src/src/Storages/MergeTree/MergeTreeData.cpp:1449: DB::(anonymous namespace)::checkVersionColumnTypesConversion(DB::IDataType const*, DB::IDataType const*, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >) @ 0x1c2585d7 in /mnt/disk4/hewenting/ClickHouse/build-dbgsrc-clang-dev-nested/programs/clickhouse-server 2021.04.22 09:48:03.714451 [ 2705 ] {} <Fatal> BaseDaemon: 5. /mnt/disk4/hewenting/ClickHouse/src/src/Storages/MergeTree/MergeTreeData.cpp:1582: DB::MergeTreeData::checkAlterIsPossible(DB::AlterCommands const&, std::__1::shared_ptr<DB::Context>) const @ 0x1c254f66 in /mnt/disk4/hewenting/ClickHouse/build-dbgsrc-clang-dev-nested/programs/clickhouse-server 2021.04.22 09:48:04.692949 [ 2705 ] {} <Fatal> BaseDaemon: 6. /mnt/disk4/hewenting/ClickHouse/src/src/Interpreters/InterpreterAlterQuery.cpp:144: DB::InterpreterAlterQuery::execute() @ 0x1bb7e403 in /mnt/disk4/hewenting/ClickHouse/build-dbgsrc-clang-dev-nested/programs/clickhouse-server. #23483 (hexiaoting).
• Backported in #24744: Fix columns function when multiple joins in select query. Closes #22736. #23501 (Maksim Kita).
• Backported in #24711: Fix misinterpretation of some LIKE expressions with escape sequences. #23610 (Alexey Milovidov).
• Backported in #24709: Fixed a bug in recovery of staled ReplicatedMergeTree replica. Some metadata updates could be ignored by staled replica if ALTER query was executed during downtime of the replica. #23742 (Alexander Tokmakov).
• Backported in #24708: Fix SIGSEGV for external GROUP BY and overflow row (i.e. queries like SELECT FROM GROUP BY WITH TOTALS SETTINGS max_bytes_before_external_group_by>0, max_rows_to_group_by>0, group_by_overflow_mode='any', totals_mode='before_having'). #23962 (Azat Khuzhin).
• Backported in #24707: Fix crash in MergeJoin, close #24010. #24013 (Vladimir C).
• Backported in #24760: Fix race condition which could happen in RBAC under a heavy load. This PR fixes #24090, #24134,. #24176 (Vitaly Baranov).
• Backported in #24704: Fixed a bug in moving Materialized View from Ordinary to Atomic database (RENAME TABLE query). Now inner table is moved to new database together with Materialized View. Fixes #23926. #24309 (Alexander Tokmakov).
• Backported in #24823: - Fixed the deadlock that can happen during LDAP role (re)mapping, when LDAP group is mapped to a nonexistent local role. #24431 (Denis Glazachev).
• Backported in #25575: Fix incorrect monotonicity of toWeek function. This fixes #24422 . This bug was introduced in https://github.com/ClickHouse/ClickHouse/pull/5212 , and was exposed later by smarter partition pruner. #24446 (Amos Bird).
• Backported in #24701: Fixed the behavior when query SYSTEM RESTART REPLICA or SYSTEM SYNC REPLICA is being processed infinitely. This was detected on server with extremely little amount of RAM. #24457 (Nikita Mikhaylov).
• Backported in #24852: Fix bug when exception Mutation was killed can be thrown to the client on mutation wait when mutation not loaded into memory yet. #24809 (alesapin).
• Backported in #25184: 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} 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 (Vladimir Chebotarev).
• Backported in #24951: Fix possible heap-buffer-overflow in Arrow. #24922 (Kruglov Pavel).
• Backported in #25209: Fix crash in query with cross join and joined_subquery_requires_alias = 0. Fixes #24011. #25082 (Nikolai Kochetov).
• Backported in #25350: Fix TOCTOU error in installation script. #25277 (Alexey Milovidov).
• Backported in #25354: Fix Logical Error Cannot sum Array/Tuple in min/maxMap. #25298 (Kruglov Pavel).
• Backported in #25503: Fix segfault when sharding_key is absent in task config for copier. #25419 (Nikita Mikhaylov).
• Backported in #25713: Fixed No such file or directory error on moving Distributed table between databases. Fixes #24971. #25667 (Alexander Tokmakov).
• Backported in #26145: Fix possible crash in pointInPolygon if the setting validate_polygons is turned off. #26113 (Alexey Milovidov).