2020 Changelog

#### Build/Testing/Packaging Improvement[​](#buildtestingpackaging-improvement-17 "Direct link to Build/Testing/Packaging Improvement")

- Fix several flaky integration tests. [#11355](https://github.com/ClickHouse/ClickHouse/pull/11355) ([alesapin](https://github.com/alesapin)).

### ClickHouse release v20.3.10.75-lts 2020-05-23[​](#clickhouse-release-v2031075-lts-2020-05-23 "Direct link to ClickHouse release v20.3.10.75-lts 2020-05-23")

#### Bug Fix[​](#bug-fix-41 "Direct link to Bug Fix")

- Removed logging from mutation finalization task if nothing was finalized. [#11109](https://github.com/ClickHouse/ClickHouse/pull/11109) ([alesapin](https://github.com/alesapin)).
- Fixed `parseDateTime64BestEffort` argument resolution bugs. [#11038](https://github.com/ClickHouse/ClickHouse/pull/11038) ([Vasily Nemkov](https://github.com/Enmk)).
- Fixed incorrect raw data size in method `getRawData()`. [#10964](https://github.com/ClickHouse/ClickHouse/pull/10964) ([Igr](https://github.com/ObjatieGroba)).
- Fixed incompatibility of two-level aggregation between versions 20.1 and earlier. This incompatibility happens when different versions of ClickHouse are used on initiator node and remote nodes and the size of `GROUP BY` result is large and aggregation is performed by a single `String` field. It leads to several unmerged rows for a single key in result. [#10952](https://github.com/ClickHouse/ClickHouse/pull/10952) ([alexey-milovidov](https://github.com/alexey-milovidov)).
- Fixed backward compatibility with tuples in `Distributed` tables. [#10889](https://github.com/ClickHouse/ClickHouse/pull/10889) ([Anton Popov](https://github.com/CurtizJ)).
- Fixed `SIGSEGV` in `StringHashTable` if such a key does not exist. [#10870](https://github.com/ClickHouse/ClickHouse/pull/10870) ([Azat Khuzhin](https://github.com/azat)).
- Fixed bug in `ReplicatedMergeTree` which might cause some `ALTER` on `OPTIMIZE` query to hang waiting for some replica after it become inactive. [#10849](https://github.com/ClickHouse/ClickHouse/pull/10849) ([tavplubix](https://github.com/tavplubix)).
- Fixed columns order after `Block::sortColumns()`. [#10826](https://github.com/ClickHouse/ClickHouse/pull/10826) ([Azat Khuzhin](https://github.com/azat)).
- Fixed the issue with `ODBC` bridge when no quoting of identifiers is requested. Fixes [#7984](https://github.com/ClickHouse/ClickHouse/issues/7984). [#10821](https://github.com/ClickHouse/ClickHouse/pull/10821) ([alexey-milovidov](https://github.com/alexey-milovidov)).
- Fixed `UBSan` and `MSan` report in `DateLUT`. [#10798](https://github.com/ClickHouse/ClickHouse/pull/10798) ([alexey-milovidov](https://github.com/alexey-milovidov)).
- Fixed incorrect type conversion in key conditions. Fixes [#6287](https://github.com/ClickHouse/ClickHouse/issues/6287). [#10791](https://github.com/ClickHouse/ClickHouse/pull/10791) ([Andrew Onyshchuk](https://github.com/oandrew))
- Fixed `parallel_view_processing` behavior. Now all insertions into `MATERIALIZED VIEW` without exception should be finished if exception happened. Fixes [#10241](https://github.com/ClickHouse/ClickHouse/issues/10241). [#10757](https://github.com/ClickHouse/ClickHouse/pull/10757) ([Nikolai Kochetov](https://github.com/KochetovNicolai)).
- Fixed combinator -`OrNull` and `-OrDefault` when combined with `-State`. [#10741](https://github.com/ClickHouse/ClickHouse/pull/10741) ([hcz](https://github.com/hczhcz)).
- Fixed crash in `generateRandom` with nested types. Fixes [#10583](https://github.com/ClickHouse/ClickHouse/issues/10583). [#10734](https://github.com/ClickHouse/ClickHouse/pull/10734) ([Nikolai Kochetov](https://github.com/KochetovNicolai)).
- Fixed data corruption for `LowCardinality(FixedString)` key column in `SummingMergeTree` which could have happened after merge. Fixes [#10489](https://github.com/ClickHouse/ClickHouse/issues/10489). [#10721](https://github.com/ClickHouse/ClickHouse/pull/10721) ([Nikolai Kochetov](https://github.com/KochetovNicolai)).
- Fixed possible buffer overflow in function `h3EdgeAngle`. [#10711](https://github.com/ClickHouse/ClickHouse/pull/10711) ([alexey-milovidov](https://github.com/alexey-milovidov)).
- Fixed disappearing totals. Totals could have being filtered if query had had join or subquery with external where condition. Fixes [#10674](https://github.com/ClickHouse/ClickHouse/issues/10674). [#10698](https://github.com/ClickHouse/ClickHouse/pull/10698) ([Nikolai Kochetov](https://github.com/KochetovNicolai)).
- Fixed multiple usages of `IN` operator with the identical set in one query. [#10686](https://github.com/ClickHouse/ClickHouse/pull/10686) ([Anton Popov](https://github.com/CurtizJ)).
- Fixed bug, which causes http requests stuck on client close when `readonly=2` and `cancel_http_readonly_queries_on_client_close=1`. Fixes [#7939](https://github.com/ClickHouse/ClickHouse/issues/7939), [#7019](https://github.com/ClickHouse/ClickHouse/issues/7019), [#7736](https://github.com/ClickHouse/ClickHouse/issues/7736), [#7091](https://github.com/ClickHouse/ClickHouse/issues/7091). [#10684](https://github.com/ClickHouse/ClickHouse/pull/10684) ([tavplubix](https://github.com/tavplubix)).
- Fixed order of parameters in `AggregateTransform` constructor. [#10667](https://github.com/ClickHouse/ClickHouse/pull/10667) ([palasonic1](https://github.com/palasonic1)).
- Fixed the lack of parallel execution of remote queries with `distributed_aggregation_memory_efficient` enabled. Fixes [#10655](https://github.com/ClickHouse/ClickHouse/issues/10655). [#10664](https://github.com/ClickHouse/ClickHouse/pull/10664) ([Nikolai Kochetov](https://github.com/KochetovNicolai)).
- Fixed possible incorrect number of rows for queries with `LIMIT`. Fixes [#10566](https://github.com/ClickHouse/ClickHouse/issues/10566), [#10709](https://github.com/ClickHouse/ClickHouse/issues/10709). [#10660](https://github.com/ClickHouse/ClickHouse/pull/10660) ([Nikolai Kochetov](https://github.com/KochetovNicolai)).
- Fixed a bug which locks concurrent alters when table has a lot of parts. [#10659](https://github.com/ClickHouse/ClickHouse/pull/10659) ([alesapin](https://github.com/alesapin)).
- Fixed a bug when on `SYSTEM DROP DNS CACHE` query also drop caches, which are used to check if user is allowed to connect from some IP addresses. [#10608](https://github.com/ClickHouse/ClickHouse/pull/10608) ([tavplubix](https://github.com/tavplubix)).
- Fixed incorrect scalar results inside inner query of `MATERIALIZED VIEW` in case if this query contained dependent table. [#10603](https://github.com/ClickHouse/ClickHouse/pull/10603) ([Nikolai Kochetov](https://github.com/KochetovNicolai)).
- Fixed `SELECT` of column `ALIAS` which default expression type different from column type. [#10563](https://github.com/ClickHouse/ClickHouse/pull/10563) ([Azat Khuzhin](https://github.com/azat)).
- Implemented comparison between DateTime64 and String values. [#10560](https://github.com/ClickHouse/ClickHouse/pull/10560) ([Vasily Nemkov](https://github.com/Enmk)).
- Fixed index corruption, which may occur in some cases after merge compact parts into another compact part. [#10531](https://github.com/ClickHouse/ClickHouse/pull/10531) ([Anton Popov](https://github.com/CurtizJ)).
- Fixed the situation, when mutation finished all parts, but hung up in `is_done=0`. [#10526](https://github.com/ClickHouse/ClickHouse/pull/10526) ([alesapin](https://github.com/alesapin)).
- Fixed overflow at beginning of unix epoch for timezones with fractional offset from `UTC`. This fixes [#9335](https://github.com/ClickHouse/ClickHouse/issues/9335). [#10513](https://github.com/ClickHouse/ClickHouse/pull/10513) ([alexey-milovidov](https://github.com/alexey-milovidov)).
- Fixed improper shutdown of `Distributed` storage. [#10491](https://github.com/ClickHouse/ClickHouse/pull/10491) ([Azat Khuzhin](https://github.com/azat)).
- Fixed numeric overflow in `simpleLinearRegression` over large integers. [#10474](https://github.com/ClickHouse/ClickHouse/pull/10474) ([hcz](https://github.com/hczhcz)).