Apache Kudu is am open-source column-oriented data store for the Hadoop ecosystem.
Relational
Decomposition Storage Model (Columnar)
In-Memory
https://kudu.apache.org/
https://github.com/apache/kudu
https://kudu.apache.org/docs/
Cloudera
US
2016
Commercial, Open Source
Linux
Apache v2
https://en.wikipedia.org/wiki/Apache_Kudu