This topic describes the release notes for ClickHouse.

May 2021

Feature Description References
Selection of scale-out methods Simple expansion is supported for scale-out. You can select one of the following scale-out methods:
  • Migration-based expansion
  • Simple expansion
Scale-out or scale-in
Upgrade of the MaterializeMySQL engine
  • The JSON, TIME, and YEAR data types are supported.
  • Bugs related to keywords and table creation for incremental data are fixed.
  • The following parameters are supported:
    • skip_error_count
    • alter include_tables
MaterializeMySQL engine
Performance optimization for scale-in and scale-out clickhouse-copier is optimized to improve the scaling efficiency. Change configurations and scale resources

March 2021

Feature Description References
Backup and recovery The backup and restoration feature is released. This feature helps avoid accidental data loss and improve data security. Backup and restoration

February 2021

Feature Description References
Tiered storage of cold and hot data Cold and hot data can be automatically migrated. This reduces storage costs by more than 80% without performance compromises. Tiered storage of hot data and cold data
PL2 and PL3 enhanced SSDs (ESSDs) PL2 and PL3 ESSDs can be used to store data and greatly improve I/O throughput. None
Disk encryption All cluster data on disks is encrypted based on block storage to ensure that your data cannot be accessed even if it is leaked. Disk encryption

November 2020

Feature Description References
Availability in the China (Hohhot) and China (Hong Kong) regions None None
Optimization of log shipping Log data in Log Service can be shipped to ApsaraDB for ClickHouse for real-time analysis. Synchronize data from Log Service

October 2020

Feature Description References
Availability in the China (Zhangjiakou), China (Chengdu), and Japan (Tokyo) regions None None
Management of accounts and permissions on databases and data dictionaries in the console Accounts can be created and passwords can be modified in the console. Permissions on databases and data dictionaries can also be modified for new and existing accounts. Manage accounts
Modification of global parameters Global parameters can be modified in the ApsaraDB for ClickHouse console. To apply the modifications, restart your cluster. Modify parameters in config.xml

August 2020

Feature Description References
Balanced data distribution during scaling Data is evenly distributed when nodes are added to a cluster. This prevents data skew issues. None
Query management Slow SQL queries can be identified and running queries can be terminated. Manage queries
A new specification of 4 cores and 16 GB memory A new specification is added to improve the processing capability of individual nodes. The new specification is 4 cores and 16 GB memory. Specifications and pricing
Data dictionary Data dictionaries can be configured in the console. If constant data exists or the data table can be split into fact tables and dimension tables, data dictionaries can be used as a substitute for dimension tables. This way, you can query data dictionaries to obtain dimension data. This improves the query efficiency. Manage dictionaries
Resource queue In open source ClickHouse, a single query that consumes large amounts of resources may cause instance downtime. Resource queues are used to resolve this issue. Resource queues in ApsaraDB for ClickHouse

July 2020

Feature Description References
Integration with Quick BI ApsaraDB for ClickHouse instances can be added as data sources to Quick BI to build business intelligence (BI) systems. Quick BI

June 2020

Feature Description References
ClickHouse V20.3.10.75 ClickHouse V20.3.10.75 is released to fix kernel bugs and enhance stability. None
Migration and real-time synchronization of data in MySQL databases Data in MySQL databases can be migrated and synchronized to ApsaraDB for ClickHouse instances in real time. This way, you can analyze business data in real time in an interactive manner. Import data from an ApsaraDB RDS for MySQL instance.
Online log shipping and analysis Enterprise users need only to create shipping tasks in the console, and deliver log data of user behavior from Log Service to ApsaraDB for ClickHouse online. This way, multi-dimensional log data analysis can be performed online by using . Synchronize data from Log Service

May 2020

Feature Description References
Integration with DMS is integrated with Data Management (DMS). This way, you can manage databases and tables, query data, and orchestrate and schedule SQL tasks online. None

February 2020

Feature Description References
New cluster types The C4, C24, C64, and C104 cluster types are available. HTTP ports are enabled. Specifications and pricing