2019 Changelog

### ClickHouse Release 19.17.4.11, 2019-11-22[​](#clickhouse-release-v19-17-4-11-2019-11-22 "Direct link to ClickHouse Release 19.17.4.11, 2019-11-22")

#### Backward Incompatible Change[​](#backward-incompatible-change "Direct link to Backward Incompatible Change")

- Using column instead of AST to store scalar subquery results for better performance. Setting `enable_scalar_subquery_optimization` was added in 19.17 and it was enabled by default. It leads to errors like [this](https://github.com/ClickHouse/ClickHouse/issues/7851) during upgrade to 19.17.2 or 19.17.3 from previous versions. This setting was disabled by default in 19.17.4, to make possible upgrading from 19.16 and older versions without errors. [#7392](https://github.com/ClickHouse/ClickHouse/pull/7392) ([Amos Bird](https://github.com/amosbird))

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

- Add the ability to create dictionaries with DDL queries. [#7360](https://github.com/ClickHouse/ClickHouse/pull/7360) ([alesapin](https://github.com/alesapin))
- Make `bloom_filter` type of index supporting `LowCardinality` and `Nullable` [#7363](https://github.com/ClickHouse/ClickHouse/issues/7363) [#7561](https://github.com/ClickHouse/ClickHouse/pull/7561) ([Nikolai Kochetov](https://github.com/KochetovNicolai))
- Add function `isValidJSON` to check that passed string is a valid json. [#5910](https://github.com/ClickHouse/ClickHouse/issues/5910) [#7293](https://github.com/ClickHouse/ClickHouse/pull/7293) ([Vdimir](https://github.com/Vdimir))
- Implement `arrayCompact` function [#7328](https://github.com/ClickHouse/ClickHouse/pull/7328) ([Memo](https://github.com/Joeywzr))
- Created function `hex` for Decimal numbers. It works like `hex(reinterpretAsString())`, but does not delete last zero bytes. [#7355](https://github.com/ClickHouse/ClickHouse/pull/7355) ([Mikhail Korotov](https://github.com/millb))
- Add `arrayFill` and `arrayReverseFill` functions, which replace elements by other elements in front/back of them in the array. [#7380](https://github.com/ClickHouse/ClickHouse/pull/7380) ([hcz](https://github.com/hczhcz))
- Add `CRC32IEEE()`/`CRC64()` support [#7480](https://github.com/ClickHouse/ClickHouse/pull/7480) ([Azat Khuzhin](https://github.com/azat))
- Implement `char` function similar to one in [mysql](https://dev.mysql.com/doc/refman/8.0/en/string-functions.html#function_char) [#7486](https://github.com/ClickHouse/ClickHouse/pull/7486) ([sundyli](https://github.com/sundy-li))
- Add `bitmapTransform` function. It transforms an array of values in a bitmap to another array of values, the result is a new bitmap [#7598](https://github.com/ClickHouse/ClickHouse/pull/7598) ([Zhichang Yu](https://github.com/yuzhichang))
- Implemented `javaHashUTF16LE()` function [#7651](https://github.com/ClickHouse/ClickHouse/pull/7651) ([achimbab](https://github.com/achimbab))
- Add `_shard_num` virtual column for the Distributed engine [#7624](https://github.com/ClickHouse/ClickHouse/pull/7624) ([Azat Khuzhin](https://github.com/azat))

#### Experimental Feature[​](#experimental-feature "Direct link to Experimental Feature")

- Support for processors (new query execution pipeline) in `MergeTree`. [#7181](https://github.com/ClickHouse/ClickHouse/pull/7181) ([Nikolai Kochetov](https://github.com/KochetovNicolai))

#### Bug Fix[​](#bug-fix-1 "Direct link to Bug Fix")

- Fix incorrect float parsing in `Values` [#7817](https://github.com/ClickHouse/ClickHouse/issues/7817) [#7870](https://github.com/ClickHouse/ClickHouse/pull/7870) ([tavplubix](https://github.com/tavplubix))
- Fix rare deadlock which can happen when trace\_log is enabled. [#7838](https://github.com/ClickHouse/ClickHouse/pull/7838) ([filimonov](https://github.com/filimonov))
- Prevent message duplication when producing Kafka table has any MVs selecting from it [#7265](https://github.com/ClickHouse/ClickHouse/pull/7265) ([Ivan](https://github.com/abyss7))
- Support for `Array(LowCardinality(Nullable(String)))` in `IN`. Resolves [#7364](https://github.com/ClickHouse/ClickHouse/issues/7364) [#7366](https://github.com/ClickHouse/ClickHouse/pull/7366) ([achimbab](https://github.com/achimbab))
- Add handling of `SQL_TINYINT` and `SQL_BIGINT`, and fix handling of `SQL_FLOAT` data source types in ODBC Bridge. [#7491](https://github.com/ClickHouse/ClickHouse/pull/7491) ([Denis Glazachev](https://github.com/traceon))
- Fix aggregation (`avg` and quantiles) over empty decimal columns [#7431](https://github.com/ClickHouse/ClickHouse/pull/7431) ([Andrey Konyaev](https://github.com/akonyaev90))
- Fix `INSERT` into Distributed with `MATERIALIZED` columns [#7377](https://github.com/ClickHouse/ClickHouse/pull/7377) ([Azat Khuzhin](https://github.com/azat))
- Make `MOVE PARTITION` work if some parts of partition are already on destination disk or volume [#7434](https://github.com/ClickHouse/ClickHouse/pull/7434) ([Vladimir Chebotarev](https://github.com/excitoon))
- Fixed bug with hardlinks failing to be created during mutations in `ReplicatedMergeTree` in multi-disk configurations. [#7558](https://github.com/ClickHouse/ClickHouse/pull/7558) ([Vladimir Chebotarev](https://github.com/excitoon))
- Fixed a bug with a mutation on a MergeTree when whole part remains unchanged and best space is being found on another disk [#7602](https://github.com/ClickHouse/ClickHouse/pull/7602) ([Vladimir Chebotarev](https://github.com/excitoon))
- Fixed bug with `keep_free_space_ratio` not being read from disks configuration [#7645](https://github.com/ClickHouse/ClickHouse/pull/7645) ([Vladimir Chebotarev](https://github.com/excitoon))
- Fix bug with table contains only `Tuple` columns or columns with complex paths. Fixes [7541](https://github.com/ClickHouse/ClickHouse/issues/7541). [#7545](https://github.com/ClickHouse/ClickHouse/pull/7545) ([alesapin](https://github.com/alesapin))
- Do not account memory for Buffer engine in max\_memory\_usage limit [#7552](https://github.com/ClickHouse/ClickHouse/pull/7552) ([Azat Khuzhin](https://github.com/azat))
- Fix final mark usage in `MergeTree` tables ordered by `tuple()`. In rare cases it could lead to `Can't adjust last granule` error while select. [#7639](https://github.com/ClickHouse/ClickHouse/pull/7639) ([Anton Popov](https://github.com/CurtizJ))
- Fix bug in mutations that have predicate with actions that require context (for example functions for json), which may lead to crashes or strange exceptions. [#7664](https://github.com/ClickHouse/ClickHouse/pull/7664) ([alesapin](https://github.com/alesapin))
- Fix mismatch of database and table names escaping in `data/` and `shadow/` directories [#7575](https://github.com/ClickHouse/ClickHouse/pull/7575) ([Alexander Burmak](https://github.com/Alex-Burmak))
- Support duplicated keys in RIGHT|FULL JOINs, e.g. `ON t.x = u.x AND t.x = u.y`. Fix crash in this case. [#7586](https://github.com/ClickHouse/ClickHouse/pull/7586) ([Artem Zuikov](https://github.com/4ertus2))
- Fix `Not found column <expression> in block` when joining on expression with RIGHT or FULL JOIN. [#7641](https://github.com/ClickHouse/ClickHouse/pull/7641) ([Artem Zuikov](https://github.com/4ertus2))
- One more attempt to fix infinite loop in `PrettySpace` format [#7591](https://github.com/ClickHouse/ClickHouse/pull/7591) ([Olga Khvostikova](https://github.com/stavrolia))
- Fix bug in `concat` function when all arguments were `FixedString` of the same size. [#7635](https://github.com/ClickHouse/ClickHouse/pull/7635) ([alesapin](https://github.com/alesapin))
- Fixed exception in case of using 1 argument while defining S3, URL and HDFS storages. [#7618](https://github.com/ClickHouse/ClickHouse/pull/7618) ([Vladimir Chebotarev](https://github.com/excitoon))
- Fix scope of the InterpreterSelectQuery for views with query [#7601](https://github.com/ClickHouse/ClickHouse/pull/7601) ([Azat Khuzhin](https://github.com/azat))

#### Improvement[​](#improvement "Direct link to Improvement")