What’s New in CQL 3.0

Cassandra 1.1 introduces significant changes in the CQL modeling and query language, necessitating a new version of the CQL language specification (CQL 3). The primary focus is on encouraging composite keys for simpler denormalization. CQL 3 allows multi-column primary keys, which are translated into wide Cassandra rows using composite column names. This change requires understanding that storage-engine rows differ from CQL rows. CQL 2 is still supported in Cassandra 1.1 for backward compatibility, but new applications should use CQL 3. The major additions to CQL include the ability to create tables with compound primary keys and perform ORDER BY operations on SELECT queries. However, direct access to column ranges via storage engine is no longer supported in CQL 3.