ClickHouse/docs/changelogs/v21.6.9.7-stable.md

ClickHouse release v21.6.9.7-stable FIXME as compared to v21.6.8.62-stable

Improvement

• Backported in #27129: If SSDDictionary is created with DDL query, it can be created only inside user_files directory. #24466 (Maksim Kita).

Bug Fix

• Backported in #26857: ParallelFormattingOutputFormat: Use mutex to handle the join to the collector_thread (https://github.com/ClickHouse/ClickHouse/issues/26694). #26703 (Raúl Marín).
• Backported in #26939: Do not remove data on ReplicatedMergeTree table shutdown to avoid creating data to metadata inconsistency. #26716 (nvartolomei).
• Backported in #26985: Aggregate function parameters might be lost when applying some combinators causing exceptions like Conversion from AggregateFunction(topKArray, Array(String)) to AggregateFunction(topKArray(10), Array(String)) is not supported. It's fixed. Fixes #26196 and #26433. #26814 (Alexander Tokmakov).
• Backported in #26910: Fix library-bridge ids load. #26834 (Kseniia Sumarokova).
• Backported in #26946: Fix error Missing columns: 'xxx' when DEFAULT column references other non materialized column without DEFAULT expression. Fixes #26591. #26900 (alesapin).
• Backported in #27000: Fix reading of custom TLDs (stops processing with lower buffer or bigger file). #26948 (Azat Khuzhin).
• Backported in #27085: Now partition ID in queries like ALTER TABLE ... PARTITION ID xxx validates for correctness. Fixes #25718. #26963 (alesapin).
• Backported in #27052: [RFC] Fix possible mutation stack due to race with DROP_RANGE. #27002 (Azat Khuzhin).
• Backported in #27159: Fix synchronization in GRPCServer This PR fixes #27024. #27064 (Vitaly Baranov).
• Backported in #27367: - Fix uninitialized memory in functions multiSearch* with empty array, close #27169. #27181 (Vladimir C).
• Backported in #27260: In rare cases system.detached_parts table might contain incorrect information for some parts, it's fixed. Fixes #27114. #27183 (Alexander Tokmakov).
• Backported in #27466: Fixed incorrect validation of partition id for MergeTree tables that created with old syntax. #27328 (Alexander Tokmakov).
• Backported in #27646: Fix incorrect result for query with row-level security, prewhere and LowCardinality filter. Fixes #27179. #27329 (Nikolai Kochetov).
• Backported in #27471: fix metric BackgroundMessageBrokerSchedulePoolTask, maybe mistyped。. #27452 (Ben).
• Fixed cache, complex_key_cache, ssd_cache, complex_key_ssd_cache configuration parsing. Options allow_read_expired_keys, max_update_queue_size, update_queue_push_timeout_milliseconds, query_wait_timeout_milliseconds were not parsed for dictionaries with non cache type. #27523 (Maksim Kita).
• Backported in #27731: Fix crash during projection materialization when some parts contain missing columns. This fixes #27512. #27528 (Amos Bird).
• Backported in #27978: Bugfix for windowFunnel's "strict" mode. This fixes #27469. #27563 (achimbab).
• Backported in #27675: Fix postgresql table function resulting in non-closing connections. Closes #26088. #27662 (Kseniia Sumarokova).
• Backported in #27699: Fix bad type cast when functions like arrayHas are applied to arrays of LowCardinality of Nullable of different non-numeric types like DateTime and DateTime64. In previous versions bad cast occurs. In new version it will lead to exception. This closes #26330. #27682 (Alexey Milovidov).
• Backported in #27746: Remove duplicated source files in CMakeLists.txt in arrow-cmake. #27736 (李扬).
• Backported in #27865: Prevent crashes for some formats when NULL (tombstone) message was coming from Kafka. Closes #19255. #27794 (filimonov).
• Backported in #28348: Fix a rare bug in DROP PART which can lead to the error Unexpected merged part intersects drop range. #27807 (alesapin).
• Backported in #27957: Fix selecting with extremes from a column of the type LowCardinality(UUID). #27918 (Vitaly Baranov).
• Backported in #27952: Check cluster name before creating Distributed table, do not allow to create a table with incorrect cluster name. Fixes #27832. #27927 (Alexander Tokmakov).
• Backported in #28206: Fix cases, when read buffer fails with 'attempt to read after end of file'. Closes #26149. #28150 (Filatenkov Artur).

Build/Testing/Packaging Improvement

• Backported in #28030: Temporarily switched ubuntu apt repository to mirror ru.archive.ubuntu.com as default one(archive.ubuntu.com) is not responding from our CI. #28016 (Ilya Yatsishin).

Bug Fix (user-visible misbehaviour in official stable or prestable release)

• Backported in #28119: Fix extremely rare segfaults on shutdown due to incorrect order of context/config reloader shutdown. #28088 (nvartolomei).
• Backported in #28179: Fixed possible excessive number of conditions moved from WHERE to PREWHERE (optimization controlled by settings optimize_move_to_prewhere). #28139 (lthaooo).
• Backported in #28256: Fix incorrect behavior in clickhouse-keeper when list watches (getChildren) triggered with set requests for children. #28190 (alesapin).
• Backported in #28264: Fix possible read of uninitialized memory for queries with Nullable(LowCardinality) type and extremes. Fixes #28165. #28205 (Nikolai Kochetov).
• Backported in #28291: Fix inconsistent result in queries with ORDER BY and Merge tables with enabled setting optimize_read_in_order. #28266 (Anton Popov).