Clickhouse

ClickHouse OSS is easy to start and fast on one node. The hidden cost appears when growth turns one node into shards, replicas, Keeper, and a distributed system your team must operate.

Three-part series on making row updates fast in a column store: purpose-built engines (ReplacingMergeTree and friends), SQL-style UPDATEs, and benchmarks claiming 1,000× speedups over the old mutation path.