  Apache Hive is an open-source relational database system for analytic
big-data workloads. In this paper we describe the key innovations on the
journey from batch tool to fully fledged enterprise data warehousing system. We
present a hybrid architecture that combines traditional MPP techniques with
more recent big data and cloud concepts to achieve the scale and performance
required by today's analytic applications. We explore the system by detailing
enhancements along four main axis: Transactions, optimizer, runtime, and
federation. We then provide experimental results to demonstrate the performance
of the system for typical workloads and conclude with a look at the community
roadmap.
