What is Clickhouse

Advantages

High speed

The implementation of ClickHouse on the Yandex.Metrica service marks the following indicators: up to 1 billion rows per second on a single server and up to 2 TB per second on a cluster of 400 nodes. Such performance is associated with columnar data storage, physical sorting of data by primary key, parallelization of operations on several processor cores of one server, and support for approximate calculations.

Linear scalability

Cross Data Center Replication is possible in ClickHouse, which replicates data between clusters, providing failover protection and high-performance data access for globally distributed and mission-critical Big Data applications.

Extensibility

ClickHouse supports a structured query language dialect close to the ANSI SQL standard, with extensions including arrays and nested data structures, URI function, and the ability to connect external key-value storage.

High availability and fault tolerance

Due to decentralisation and the absence of a single point of failure, ClickHouse works reliably in a distributed cluster. The DBMS maintains the complete identity of data on different replicas, automatically recovering them after failures.

Ease of deployment and convenience of use

As a means of connecting to the DBMS, you can use the console, HTTP API, JDBC and ODBC drivers, as well as many “wrappers” in Python, PHP, NodeJS, Perl, Ruby, and R.