2020 Changelog

- Fix ALTER of tables with compact parts. [#10130](https://github.com/ClickHouse/ClickHouse/pull/10130) ([Anton Popov](https://github.com/CurtizJ))
- Add the ability to relax the restriction on non-deterministic functions usage in mutations with `allow_nondeterministic_mutations` setting. [#10186](https://github.com/ClickHouse/ClickHouse/pull/10186) ([filimonov](https://github.com/filimonov))
- Fix `DROP TABLE` invoked for dictionary [#10165](https://github.com/ClickHouse/ClickHouse/pull/10165) ([Azat Khuzhin](https://github.com/azat))
- Convert blocks if structure does not match when doing `INSERT` into Distributed table [#10135](https://github.com/ClickHouse/ClickHouse/pull/10135) ([Azat Khuzhin](https://github.com/azat))
- The number of rows was logged incorrectly (as sum across all parts) when inserted block is split by parts with partition key. [#10138](https://github.com/ClickHouse/ClickHouse/pull/10138) ([alexey-milovidov](https://github.com/alexey-milovidov))
- Add some arguments check and support identifier arguments for MySQL Database Engine [#10077](https://github.com/ClickHouse/ClickHouse/pull/10077) ([Winter Zhang](https://github.com/zhang2014))
- Fix incorrect `index_granularity_bytes` check while creating new replica. Fixes [#10098](https://github.com/ClickHouse/ClickHouse/issues/10098). [#10121](https://github.com/ClickHouse/ClickHouse/pull/10121) ([alesapin](https://github.com/alesapin))
- Fix bug in `CHECK TABLE` query when table contain skip indices. [#10068](https://github.com/ClickHouse/ClickHouse/pull/10068) ([alesapin](https://github.com/alesapin))
- Fix Distributed-over-Distributed with the only one shard in a nested table [#9997](https://github.com/ClickHouse/ClickHouse/pull/9997) ([Azat Khuzhin](https://github.com/azat))
- Fix possible rows loss for queries with `JOIN` and `UNION ALL`. Fixes [#9826](https://github.com/ClickHouse/ClickHouse/issues/9826), [#10113](https://github.com/ClickHouse/ClickHouse/issues/10113). ... [#10099](https://github.com/ClickHouse/ClickHouse/pull/10099) ([Nikolai Kochetov](https://github.com/KochetovNicolai))
- Fix bug in dictionary when local clickhouse server is used as source. It may caused memory corruption if types in dictionary and source are not compatible. [#10071](https://github.com/ClickHouse/ClickHouse/pull/10071) ([alesapin](https://github.com/alesapin))
- Fixed replicated tables startup when updating from an old ClickHouse version where `/table/replicas/replica_name/metadata` node does not exist. Fixes [#10037](https://github.com/ClickHouse/ClickHouse/issues/10037). [#10095](https://github.com/ClickHouse/ClickHouse/pull/10095) ([alesapin](https://github.com/alesapin))
- Fix error `Cannot clone block with columns because block has 0 columns ... While executing GroupingAggregatedTransform`. It happened when setting `distributed_aggregation_memory_efficient` was enabled, and distributed query read aggregating data with mixed single and two-level aggregation from different shards. [#10063](https://github.com/ClickHouse/ClickHouse/pull/10063) ([Nikolai Kochetov](https://github.com/KochetovNicolai))
- Fix deadlock when database with materialized view failed attach at start [#10054](https://github.com/ClickHouse/ClickHouse/pull/10054) ([Azat Khuzhin](https://github.com/azat))
- Fix a segmentation fault that could occur in GROUP BY over string keys containing trailing zero bytes ([#8636](https://github.com/ClickHouse/ClickHouse/issues/8636), [#8925](https://github.com/ClickHouse/ClickHouse/issues/8925)). ... [#10025](https://github.com/ClickHouse/ClickHouse/pull/10025) ([Alexander Kuzmenkov](https://github.com/akuzm))
- 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))
- Fix possible deadlock in `SYSTEM RESTART REPLICAS` [#9955](https://github.com/ClickHouse/ClickHouse/pull/9955) ([tavplubix](https://github.com/tavplubix))
- Fix the number of threads used for remote query execution (performance regression, since 20.3). This happened when query from `Distributed` table was executed simultaneously on local and remote shards. Fixes [#9965](https://github.com/ClickHouse/ClickHouse/issues/9965) [#9971](https://github.com/ClickHouse/ClickHouse/pull/9971) ([Nikolai Kochetov](https://github.com/KochetovNicolai))
- Fixed `DeleteOnDestroy` logic in `ATTACH PART` which could lead to automatic removal of attached part and added few tests [#9410](https://github.com/ClickHouse/ClickHouse/pull/9410) ([Vladimir Chebotarev](https://github.com/excitoon))
- Fix a bug with `ON CLUSTER` DDL queries freezing on server startup. [#9927](https://github.com/ClickHouse/ClickHouse/pull/9927) ([Gagan Arneja](https://github.com/garneja))
- Fix bug in which the necessary tables weren't retrieved at one of the processing stages of queries to some databases. Fixes [#9699](https://github.com/ClickHouse/ClickHouse/issues/9699). [#9949](https://github.com/ClickHouse/ClickHouse/pull/9949) ([achulkov2](https://github.com/achulkov2))
- Fix 'Not found column in block' error when `JOIN` appears with `TOTALS`. Fixes [#9839](https://github.com/ClickHouse/ClickHouse/issues/9839) [#9939](https://github.com/ClickHouse/ClickHouse/pull/9939) ([Artem Zuikov](https://github.com/4ertus2))
- Fix parsing multiple hosts set in the CREATE USER command [#9924](https://github.com/ClickHouse/ClickHouse/pull/9924) ([Vitaly Baranov](https://github.com/vitlibar))
- Fix `TRUNCATE` for Join table engine ([#9917](https://github.com/ClickHouse/ClickHouse/issues/9917)). [#9920](https://github.com/ClickHouse/ClickHouse/pull/9920) ([Amos Bird](https://github.com/amosbird))
- Fix race condition between drop and optimize in `ReplicatedMergeTree`. [#9901](https://github.com/ClickHouse/ClickHouse/pull/9901) ([alesapin](https://github.com/alesapin))
- Fix `DISTINCT` for Distributed when `optimize_skip_unused_shards` is set. [#9808](https://github.com/ClickHouse/ClickHouse/pull/9808) ([Azat Khuzhin](https://github.com/azat))
- Fix "scalar does not exist" error in ALTERs ([#9878](https://github.com/ClickHouse/ClickHouse/issues/9878)). ... [#9904](https://github.com/ClickHouse/ClickHouse/pull/9904) ([Amos Bird](https://github.com/amosbird))
- Fix error with qualified names in `distributed_product_mode=\'local\'`. Fixes [#4756](https://github.com/ClickHouse/ClickHouse/issues/4756) [#9891](https://github.com/ClickHouse/ClickHouse/pull/9891) ([Artem Zuikov](https://github.com/4ertus2))
- For INSERT queries shards now do clamp the settings from the initiator to their constraints instead of throwing an exception. This fix allows to send INSERT queries to a shard with another constraints. This change improves fix [#9447](https://github.com/ClickHouse/ClickHouse/issues/9447). [#9852](https://github.com/ClickHouse/ClickHouse/pull/9852) ([Vitaly Baranov](https://github.com/vitlibar))
- Add some retries when commiting offsets to Kafka broker, since it can reject commit if during `offsets.commit.timeout.ms` there were no enough replicas available for the `__consumer_offsets` topic [#9884](https://github.com/ClickHouse/ClickHouse/pull/9884) ([filimonov](https://github.com/filimonov))
- Fix Distributed engine behavior when virtual columns of the underlying table used in `WHERE` [#9847](https://github.com/ClickHouse/ClickHouse/pull/9847) ([Azat Khuzhin](https://github.com/azat))
- Fixed some cases when timezone of the function argument wasn't used properly. [#9574](https://github.com/ClickHouse/ClickHouse/pull/9574) ([Vasily Nemkov](https://github.com/Enmk))
- Fix 'Different expressions with the same alias' error when query has PREWHERE and WHERE on distributed table and `SET distributed_product_mode = 'local'`. [#9871](https://github.com/ClickHouse/ClickHouse/pull/9871) ([Artem Zuikov](https://github.com/4ertus2))