2020 Changelog

#### Performance Improvement[​](#performance-improvement-13 "Direct link to Performance Improvement")

- Index not used for IN operator with literals, performance regression introduced around v19.3. This fixes [#10574](https://github.com/ClickHouse/ClickHouse/issues/10574). [#12062](https://github.com/ClickHouse/ClickHouse/pull/12062) ([nvartolomei](https://github.com/nvartolomei)).

### ClickHouse release v20.3.12.112-lts 2020-06-25[​](#clickhouse-release-v20312112-lts-2020-06-25 "Direct link to ClickHouse release v20.3.12.112-lts 2020-06-25")

#### Bug Fix[​](#bug-fix-39 "Direct link to Bug Fix")

- Fix rare crash caused by using `Nullable` column in prewhere condition. Continuation of [#11608](https://github.com/ClickHouse/ClickHouse/issues/11608). [#11869](https://github.com/ClickHouse/ClickHouse/pull/11869) ([Nikolai Kochetov](https://github.com/KochetovNicolai)).
- Don't allow arrayJoin inside higher order functions. It was leading to broken protocol synchronization. This closes [#3933](https://github.com/ClickHouse/ClickHouse/issues/3933). [#11846](https://github.com/ClickHouse/ClickHouse/pull/11846) ([alexey-milovidov](https://github.com/alexey-milovidov)).
- Fix using too many threads for queries. [#11788](https://github.com/ClickHouse/ClickHouse/pull/11788) ([Nikolai Kochetov](https://github.com/KochetovNicolai)).
- Fix unexpected behaviour of queries like `SELECT *, xyz.*` which were success while an error expected. [#11753](https://github.com/ClickHouse/ClickHouse/pull/11753) ([hexiaoting](https://github.com/hexiaoting)).
- Now replicated fetches will be cancelled during metadata alter. [#11744](https://github.com/ClickHouse/ClickHouse/pull/11744) ([alesapin](https://github.com/alesapin)).
- Fixed LOGICAL\_ERROR caused by wrong type deduction of complex literals in Values input format. [#11732](https://github.com/ClickHouse/ClickHouse/pull/11732) ([tavplubix](https://github.com/tavplubix)).
- Fix `ORDER BY ... WITH FILL` over const columns. [#11697](https://github.com/ClickHouse/ClickHouse/pull/11697) ([Anton Popov](https://github.com/CurtizJ)).
- Pass proper timeouts when communicating with XDBC bridge. Recently timeouts were not respected when checking bridge liveness and receiving meta info. [#11690](https://github.com/ClickHouse/ClickHouse/pull/11690) ([alexey-milovidov](https://github.com/alexey-milovidov)).
- Fix error which leads to an incorrect state of `system.mutations`. It may show that whole mutation is already done but the server still has `MUTATE_PART` tasks in the replication queue and tries to execute them. This fixes [#11611](https://github.com/ClickHouse/ClickHouse/issues/11611). [#11681](https://github.com/ClickHouse/ClickHouse/pull/11681) ([alesapin](https://github.com/alesapin)).
- Add support for regular expressions with case-insensitive flags. This fixes [#11101](https://github.com/ClickHouse/ClickHouse/issues/11101) and fixes [#11506](https://github.com/ClickHouse/ClickHouse/issues/11506). [#11649](https://github.com/ClickHouse/ClickHouse/pull/11649) ([alexey-milovidov](https://github.com/alexey-milovidov)).
- Remove trivial count query optimization if row-level security is set. In previous versions the user get total count of records in a table instead filtered. This fixes [#11352](https://github.com/ClickHouse/ClickHouse/issues/11352). [#11644](https://github.com/ClickHouse/ClickHouse/pull/11644) ([alexey-milovidov](https://github.com/alexey-milovidov)).
- Fix bloom filters for String (data skipping indices). [#11638](https://github.com/ClickHouse/ClickHouse/pull/11638) ([Azat Khuzhin](https://github.com/azat)).
- Fix rare crash caused by using `Nullable` column in prewhere condition. (Probably it is connected with [#11572](https://github.com/ClickHouse/ClickHouse/issues/11572) somehow). [#11608](https://github.com/ClickHouse/ClickHouse/pull/11608) ([Nikolai Kochetov](https://github.com/KochetovNicolai)).
- Fix error `Block structure mismatch` for queries with sampling reading from `Buffer` table. [#11602](https://github.com/ClickHouse/ClickHouse/pull/11602) ([Nikolai Kochetov](https://github.com/KochetovNicolai)).
- Fix wrong exit code of the clickhouse-client, when exception.code() % 256 = 0. [#11601](https://github.com/ClickHouse/ClickHouse/pull/11601) ([filimonov](https://github.com/filimonov)).
- Fix trivial error in log message about "Mark cache size was lowered" at server startup. This closes [#11399](https://github.com/ClickHouse/ClickHouse/issues/11399). [#11589](https://github.com/ClickHouse/ClickHouse/pull/11589) ([alexey-milovidov](https://github.com/alexey-milovidov)).
- Fix error `Size of offsets does not match size of column` for queries with `PREWHERE column in (subquery)` and `ARRAY JOIN`. [#11580](https://github.com/ClickHouse/ClickHouse/pull/11580) ([Nikolai Kochetov](https://github.com/KochetovNicolai)).
- All queries in HTTP session have had the same query\_id. It is fixed. [#11578](https://github.com/ClickHouse/ClickHouse/pull/11578) ([tavplubix](https://github.com/tavplubix)).
- Now clickhouse-server docker container will prefer IPv6 checking server aliveness. [#11550](https://github.com/ClickHouse/ClickHouse/pull/11550) ([Ivan Starkov](https://github.com/istarkov)).
- Fix shard\_num/replica\_num for `<node>` (breaks use\_compact\_format\_in\_distributed\_parts\_names). [#11528](https://github.com/ClickHouse/ClickHouse/pull/11528) ([Azat Khuzhin](https://github.com/azat)).
- Fix memory leak when exception is thrown in the middle of aggregation with -State functions. This fixes [#8995](https://github.com/ClickHouse/ClickHouse/issues/8995). [#11496](https://github.com/ClickHouse/ClickHouse/pull/11496) ([alexey-milovidov](https://github.com/alexey-milovidov)).
- Fix wrong results of distributed queries when alias could override qualified column name. Fixes [#9672](https://github.com/ClickHouse/ClickHouse/issues/9672) [#9714](https://github.com/ClickHouse/ClickHouse/issues/9714). [#9972](https://github.com/ClickHouse/ClickHouse/pull/9972) ([Artem Zuikov](https://github.com/4ertus2)).

### ClickHouse release v20.3.11.97-lts 2020-06-10[​](#clickhouse-release-v2031197-lts-2020-06-10 "Direct link to ClickHouse release v20.3.11.97-lts 2020-06-10")

#### New Feature[​](#new-feature-9 "Direct link to New Feature")

- Now ClickHouse controls timeouts of dictionary sources on its side. Two new settings added to cache dictionary configuration: `strict_max_lifetime_seconds`, which is `max_lifetime` by default and `query_wait_timeout_milliseconds`, which is one minute by default. The first settings is also useful with `allow_read_expired_keys` settings (to forbid reading very expired keys). [#10337](https://github.com/ClickHouse/ClickHouse/pull/10337) ([Nikita Mikhaylov](https://github.com/nikitamikhaylov)).

#### Bug Fix[​](#bug-fix-40 "Direct link to Bug Fix")