ClickHouse

ClickHouse is an open-source column-oriented OLAP database built for low-latency analytical queries over high-volume data. Its columnar storage, vectorized execution, and aggressive compression target interactive, sub-second analytics rather than transactional workloads.

It ingests data at high rates — including streaming inserts from Kafka — and serves queries through a SQL dialect with rich analytical functions. Materialized views are commonly used to maintain pre-aggregated tables at insert time.

Typical usage contexts include user-facing analytics, observability and event data, and real-time dashboards where a general-purpose warehouse is too slow or too costly. It can be self-hosted or consumed as the managed ClickHouse Cloud service.