"The open source Apache Cassandra NoSQL database, since its
inception, has been focused on being highly scalable.
"With the new Cassandra 0.7 release this week, that scalability
is being improved with secondary indexes and large row support for
database rows of up to two billion columns per row.
"Apache Cassandra 0.7 follows the 0.6 release, which came out in
April of 2010. The Cassandra database was originally begun by
developers at Facebook and has since been adopted by multiple web
properties including Twitter, Digg and Reddit. Commercial support
is available by way of startup Riptano."