Up and running with cassandra. Cassandra is a hybrid non-relational database in the same class as Google’s BigTable.
It is more featureful than a key/value store like Riak, but supports fewer query types than a document store like MongoDB. Cassandra was started by Facebook and later transferred to the open-source community. It is an ideal runtime database for web-scale domains like social networks. Getting started with Tangosol Coherence ... SQL relay - persistent database connection pool.