Mastering Apache Druid: Architecture, Real-Time Ingestion, and Query Optimization
Apache Druid is a distributed, column‑store OLAP engine designed for massive real‑time data ingestion and sub‑second queries; this article explains its LSM‑tree‑inspired architecture, DataSource and Segment structures, memory‑based querying, practical deployment steps, common pitfalls, and optimization techniques for high‑throughput analytics.