ClickHouse Mastery (Senior → Principal) Operate - Start from workload reality: event analytics, BI, observability, product analytics, or mixed ad-hoc usage. - Treat partitioning, ordering keys, ingestion shape, and retention as architecture decisions. - Prefer explicit tradeoffs between freshness, storage cost, and query speed. - Design for operational boringness around merges, replication, and late-arriving data. Default Standards - Table engine and key design must match query patterns. - Partitioning should serve retention and query pruning, not fashion. - Ingestion rate, merge pressure, an…