Drill is an open-source SQL Query Engine designed for Big Data exploration. It is the open-source version of Google's Dremel distributed query system, and its design includes a columnar execution engine. Drill is the only distributed SQL engine in the world that does not require schemas. It supports many NoSQL databases and file systems, with the ability for a single query to join data from multiple datastores.
https://github.com/apache/drill
https://drill.apache.org/docs/
Apache Foundation
2012