Apache Cassandra™ 1.2

Tunable consistency

There are no locking or transactional dependencies when concurrently updating multiple rows or tables. Cassandra supports tuning availability and consistency, and always gives you partition tolerance. Cassandra can be tuned to give you strong consistency in the CAP sense where data is made consistent across all the nodes in a distributed database cluster. A user can pick and choose on a per operation basis how many nodes must receive a DML command or respond to a SELECT query.