Does ClickHouse support real-time updates?

ClickHouse supports the UPDATE statement and is capable running real-time updates as fast as it runs INSERTs.

This is possible thanks to the patch parts data structure, which allows quickly applying changes without a significant impact on the SELECT performance.

Moreover, due to MVCC (multi-version concurrency control) and snapshot isolation, updates provide ACID properties.

Info

Lightweight updates were first introduced in ClickHouse version 25.7.