About the service

Cloud ClickHouse is a ready-made solution for storing and analyzing historical data based on the columnar analytical DBMS ClickHouse developed by ClickHouse Inc.

The main advantage of this DBMS is fast processing of OLAP queries on structured big data. Cloud ClickHouse efficiently uses CPU resources and can process data stored on hard drives without fully loading that data into the memory cache.

Cloud ClickHouse uses its own SQL dialect with a number of extensions and limitations compared to standard SQL. Key extensions include the ability to work with external key-value stores (dictionaries) and aggregate functions for approximate computations. Key limitations include the absence of transactions and support for point UPDATE/DELETE (only batch UPDATE/DELETE is available), and limited JOIN syntax support.

Cloud ClickHouse is recommended when:

• you need to generate analytical reports on big data in real time — for example, calculating application customer behavior analytics;
• a large volume of incoming data is continuously written to the database, while a consistently high read query processing speed is required;
• linear scalability is important.

The list of ClickHouse versions supported in VK Cloud is available when creating an instance of this service.

For more information about ClickHouse, see the official documentation.