Apache Druid
A high performance real-time analytics database
... outperform legacy solutions. Druid combines novel storage ideas, indexing structures, and both exact and approximate queries to return most results in under a second. Druid unlocks new types of queries and workflows for clickstream, APM, supply chain, network telemetry, digital marketing, risk/fraud, and many other types of data. Druid is purpose built for rapid, ad-hoc queries on both real-time and historical data.