v.21.8
Bug Fix
38- Fix SET ROLE Behavior in Certain Cases
- Fix nullptr Dereference in Window Functions
- Fix incorrect function names for groupBitmapAnd/Or/Xor
- Fix RabbitMQ Shutdown Crash When Setup Not Started
- Fix CREATE DICTIONARY query issues with quoted names
- Fix Name Resolution Issues After Rewriting Column Aliases
- Fix infinite non-joined block stream in partial_merge_join
- Fix Crash When Logging in as Dropped User
- Fix optimize_distributed_group_by_sharding_key for Multiple Columns
- CAST Date to DateTime now respects timezone settings, improving comparisons and function results.
- Fixed Rare Bug in Lost Replica Recovery
- Fix zstd Decompression for Escape Sequences in Internal Buffer
- Fix logical error in join with totals (#26017)
- Remove Excessive Newline in thread_name Column of system.stack_trace Table
- Fix joinGet with LowCardinality columns
- Fix crash in pointInPolygon with validate_polygons setting off
- Fix Exception When Iterating Over Non-Existing Remote Directory
- Fix Rare Server Crash in ZooKeeper Client
- Fix thread count estimation for right subquery join
- Fixed sequence_id in ClickHouse MySQL protocol packets during query exceptions
- Fix Mismatched Header in Normal Projection with PREWHERE
- Fix Map Formatting with Integer Keys to JSON
- Fix Deadlock Issue in Query Profiler Stack Unwinding
- Fix dictGet() crash with invalid arguments
- Fixed scram-sha-256 authentication for PostgreSQL engines
- Fix Long Backoff for Background Tasks in Full Pool
- Fix ARM Exception Handling for Non-Default Page Size
- Fix sharding_key for remote() function to prevent column error
- Fixed Column Errors in MaterializeMySQL
- Fix optimize_skip_unused_shards_rewrite_in for non-UInt64 types
- Fix bug in DROP PART query for ReplicatedMergeTree tables
- Fix TTL Bug with GROUP BY Expression
- Allow StorageMerge to Access Tables with Aliases
- Fix Slow Dict Join Issue #24209
- Fix ALTER MODIFY COLUMN for TTL Expression Columns
- Fix PREWHERE Assertion for Non-UInt8 Type
- Fix msan crash related to fuzzing, resolves #22517
- Update chown command in ClickHouse docker entrypoint to fix Kubernetes pod restart errors
Improvement
33- Use Map Data Type for System Logs Tables in ClickHouse
- Allow Unwrapped Key Expression for dictGet and dictHas in Single-Attribute Dictionary
- Implement bin/hex Function from AggregateFunction States
- Support UUID Type for empty and notEmpty Functions
- Add support for SET SQL_SELECT_LIMIT in MySQL protocol
- More Network Instrumentation: Added Counters and Gauges for Data Transmission
- Add optimize_move_to_prewhere_if_final Setting for FINAL Query Optimization
- Allow complex quoted identifiers for JOINed tables
- Add Unicode Support in Nested Data Types
- Allow quantiles functions to work with aggregate_functions_null_for_empty
- Allow Arbitrary Expressions in Parametric Aggregate Functions
- Correct Exception Handling for Invalid Date Parsing
- Support for Multiple Includes in Configuration
- Support for Queries with Column Named `null` and ON CLUSTER
- Support LowCardinality, Decimal, and UUID for JSONExtract
- Convert History File from readline to replxx Format
- Fix intersecting parts issue after DROP PART or empty part deletion
- Better Handling of Lost Parts in ReplicatedMergeTree Tables
- Allow clickhouse-client to start with unreadable working directory
- Fix No available columns error for Merge storage
- MySQL Engine Enhances Column Comment Exchange with ClickHouse
- Fix GROUP BY Constant Behavior on Empty Set
- Cancel Running Merges on DROP PARTITION and TRUNCATE for ReplicatedMergeTree
- Support ENUM data type for MaterializeMySQL
- Support for Materialized and Aliased Columns in JOIN
- Fix race condition in ALTER TABLE DETACH and background merges
- Update NetworkReceiveElapsedMicroseconds Metric to Include Client Data Wait Time
- Support TRUNCATE TABLE for S3 and HDFS
- Support for Dynamic Reloading of Config for Thread Pool Adjustment in Background Jobs
- Allow JSONExtract to Return Non-String Elements as Strings
- Support Regex in Database Argument for StorageMerge
- Web UI: Auto-generate links for URL-like values
- Make sudo service clickhouse-server start compatible with systemd on Centos 8
New Feature
11- Add SQL/JSON Standard Support in ClickHouse
- Collect System Metrics on CPU, Disk, Memory, and More in ClickHouse
- Add MaterializedPostgreSQL Table Engine for Database Replication
- Add Padding Functions: leftPad, rightPad, leftPadUTF8, rightPadUTF8
- Add FIRST keyword to ADD INDEX command in ClickHouse
- Introduce system.data_skipping_indices table for index information
- Add bin/unbin functions
- Support additional numeric types in mapAdd and mapSubtract functions
- Support DISTINCT ON expression
- Add Reset Feature for Custom Settings to Default
- Render Pipelines as Graphs in Web UI with EXPLAIN PIPELINE Query