2018 Changelog

#### Backward Incompatible Changes:[​](#backward-incompatible-changes "Direct link to Backward Incompatible Changes:")

- Removed the ability to compare the `Date` type with a number. Instead of `toDate('2018-12-18') = 17883`, you must use explicit type conversion `= toDate(17883)` [#3687](https://github.com/ClickHouse/ClickHouse/pull/3687)

## ClickHouse Release 18.14[​](#clickhouse-release-18-14 "Direct link to ClickHouse Release 18.14")

### ClickHouse Release 18.14.19, 2018-12-19[​](#clickhouse-release-18-14-19-2018-12-19 "Direct link to ClickHouse Release 18.14.19, 2018-12-19")

#### Bug Fixes:[​](#bug-fixes-2 "Direct link to Bug Fixes:")

- Fixed an error that led to problems with updating dictionaries with the ODBC source. [#3825](https://github.com/ClickHouse/ClickHouse/issues/3825), [#3829](https://github.com/ClickHouse/ClickHouse/issues/3829)
- Databases are correctly specified when executing DDL `ON CLUSTER` queries. [#3460](https://github.com/ClickHouse/ClickHouse/pull/3460)
- Fixed a segfault if the `max_temporary_non_const_columns` limit was exceeded. [#3788](https://github.com/ClickHouse/ClickHouse/pull/3788)

#### Build Improvements:[​](#build-improvements-2 "Direct link to Build Improvements:")

- Fixes for builds on ARM.

### ClickHouse Release 18.14.18, 2018-12-04[​](#clickhouse-release-18-14-18-2018-12-04 "Direct link to ClickHouse Release 18.14.18, 2018-12-04")

#### Bug Fixes:[​](#bug-fixes-3 "Direct link to Bug Fixes:")

- Fixed error in `dictGet...` function for dictionaries of type `range`, if one of the arguments is constant and other is not. [#3751](https://github.com/ClickHouse/ClickHouse/pull/3751)
- Fixed error that caused messages `netlink: '...': attribute type 1 has an invalid length` to be printed in Linux kernel log, that was happening only on fresh enough versions of Linux kernel. [#3749](https://github.com/ClickHouse/ClickHouse/pull/3749)
- Fixed segfault in function `empty` for argument of `FixedString` type. [Daniel, Dao Quang Minh](https://github.com/ClickHouse/ClickHouse/pull/3703)
- Fixed excessive memory allocation when using large value of `max_query_size` setting (a memory chunk of `max_query_size` bytes was preallocated at once). [#3720](https://github.com/ClickHouse/ClickHouse/pull/3720)

#### Build Changes:[​](#build-changes "Direct link to Build Changes:")

- Fixed build with LLVM/Clang libraries of version 7 from the OS packages (these libraries are used for runtime query compilation). [#3582](https://github.com/ClickHouse/ClickHouse/pull/3582)

### ClickHouse Release 18.14.17, 2018-11-30[​](#clickhouse-release-18-14-17-2018-11-30 "Direct link to ClickHouse Release 18.14.17, 2018-11-30")

#### Bug Fixes:[​](#bug-fixes-4 "Direct link to Bug Fixes:")

- Fixed cases when the ODBC bridge process did not terminate with the main server process. [#3642](https://github.com/ClickHouse/ClickHouse/pull/3642)
- Fixed synchronous insertion into the `Distributed` table with a columns list that differs from the column list of the remote table. [#3673](https://github.com/ClickHouse/ClickHouse/pull/3673)
- Fixed a rare race condition that can lead to a crash when dropping a MergeTree table. [#3643](https://github.com/ClickHouse/ClickHouse/pull/3643)
- Fixed a query deadlock in case when query thread creation fails with the `Resource temporarily unavailable` error. [#3643](https://github.com/ClickHouse/ClickHouse/pull/3643)
- Fixed parsing of the `ENGINE` clause when the `CREATE AS table` syntax was used and the `ENGINE` clause was specified before the `AS table` (the error resulted in ignoring the specified engine). [#3692](https://github.com/ClickHouse/ClickHouse/pull/3692)

### ClickHouse Release 18.14.15, 2018-11-21[​](#clickhouse-release-18-14-15-2018-11-21 "Direct link to ClickHouse Release 18.14.15, 2018-11-21")

#### Bug Fixes:[​](#bug-fixes-5 "Direct link to Bug Fixes:")

- The size of memory chunk was overestimated while deserializing the column of type `Array(String)` that leads to "Memory limit exceeded" errors. The issue appeared in version 18.12.13. [#3589](https://github.com/ClickHouse/ClickHouse/issues/3589)

### ClickHouse Release 18.14.14, 2018-11-20[​](#clickhouse-release-18-14-14-2018-11-20 "Direct link to ClickHouse Release 18.14.14, 2018-11-20")

#### Bug Fixes:[​](#bug-fixes-6 "Direct link to Bug Fixes:")

- Fixed `ON CLUSTER` queries when cluster configured as secure (flag `<secure>`). [#3599](https://github.com/ClickHouse/ClickHouse/pull/3599)

#### Build Changes:[​](#build-changes-1 "Direct link to Build Changes:")

- Fixed problems (llvm-7 from system, macos) [#3582](https://github.com/ClickHouse/ClickHouse/pull/3582)

### ClickHouse Release 18.14.13, 2018-11-08[​](#clickhouse-release-18-14-13-2018-11-08 "Direct link to ClickHouse Release 18.14.13, 2018-11-08")

#### Bug Fixes:[​](#bug-fixes-7 "Direct link to Bug Fixes:")

- Fixed the `Block structure mismatch in MergingSorted stream` error. [#3162](https://github.com/ClickHouse/ClickHouse/issues/3162)
- Fixed `ON CLUSTER` queries in case when secure connections were turned on in the cluster config (the `<secure>` flag). [#3465](https://github.com/ClickHouse/ClickHouse/pull/3465)
- Fixed an error in queries that used `SAMPLE`, `PREWHERE` and alias columns. [#3543](https://github.com/ClickHouse/ClickHouse/pull/3543)
- Fixed a rare `unknown compression method` error when the `min_bytes_to_use_direct_io` setting was enabled. [3544](https://github.com/ClickHouse/ClickHouse/pull/3544)

#### Performance Improvements:[​](#performance-improvements "Direct link to Performance Improvements:")

- Fixed performance regression of queries with `GROUP BY` of columns of UInt16 or Date type when executing on AMD EPYC processors. [Igor Lapko](https://github.com/ClickHouse/ClickHouse/pull/3512)
- Fixed performance regression of queries that process long strings. [#3530](https://github.com/ClickHouse/ClickHouse/pull/3530)

#### Build Improvements:[​](#build-improvements-3 "Direct link to Build Improvements:")

- Improvements for simplifying the Arcadia build. [#3475](https://github.com/ClickHouse/ClickHouse/pull/3475), [#3535](https://github.com/ClickHouse/ClickHouse/pull/3535)

### ClickHouse Release 18.14.12, 2018-11-02[​](#clickhouse-release-18-14-12-2018-11-02 "Direct link to ClickHouse Release 18.14.12, 2018-11-02")

#### Bug Fixes:[​](#bug-fixes-8 "Direct link to Bug Fixes:")

- Fixed a crash on joining two unnamed subqueries. [#3505](https://github.com/ClickHouse/ClickHouse/pull/3505)
- Fixed generating incorrect queries (with an empty `WHERE` clause) when querying external databases. [hotid](https://github.com/ClickHouse/ClickHouse/pull/3477)
- Fixed using an incorrect timeout value in ODBC dictionaries. [Marek Vavruša](https://github.com/ClickHouse/ClickHouse/pull/3511)

### ClickHouse Release 18.14.11, 2018-10-29[​](#clickhouse-release-18-14-11-2018-10-29 "Direct link to ClickHouse Release 18.14.11, 2018-10-29")

#### Bug Fixes:[​](#bug-fixes-9 "Direct link to Bug Fixes:")

- Fixed the error `Block structure mismatch in UNION stream: different number of columns` in LIMIT queries. [#2156](https://github.com/ClickHouse/ClickHouse/issues/2156)
- Fixed errors when merging data in tables containing arrays inside Nested structures. [#3397](https://github.com/ClickHouse/ClickHouse/pull/3397)
- Fixed incorrect query results if the `merge_tree_uniform_read_distribution` setting is disabled (it is enabled by default). [#3429](https://github.com/ClickHouse/ClickHouse/pull/3429)
- Fixed an error on inserts to a Distributed table in Native format. [#3411](https://github.com/ClickHouse/ClickHouse/issues/3411)

### ClickHouse Release 18.14.10, 2018-10-23[​](#clickhouse-release-18-14-10-2018-10-23 "Direct link to ClickHouse Release 18.14.10, 2018-10-23")

- The `compile_expressions` setting (JIT compilation of expressions) is disabled by default. [#3410](https://github.com/ClickHouse/ClickHouse/pull/3410)
- The `enable_optimize_predicate_expression` setting is disabled by default.

### ClickHouse Release 18.14.9, 2018-10-16[​](#clickhouse-release-18-14-9-2018-10-16 "Direct link to ClickHouse Release 18.14.9, 2018-10-16")