Cassandra Query Language (CQL) is a SQL (Structured Query Language)-like language for querying Cassandra. Although CQL has many similarities to SQL, there are some fundamental differences. For example, the CQL adaptation to the Cassandra data model and architecture, doesn't support operations, such as JOINs, which make no sense in a non-relational database.
This reference describes the Beta version of CQL 3.0.0. For a description of CQL 2.0.0, see the CQL reference for Cassandra 1.0.
In addition to describing CQL commands, this reference includes introductory topics that briefly describe how commands are structured, the keywords and identifiers used in CQL, Cassandra data types, how to format dates and times, and CQL counterparts to Cassandra storage types. These topics are covered in the following sections.
A brief tutorial on using CQL3 commands is also provided.
The command reference covers CQL and CQLsh, which is the CQL client. Using cqlsh, you can query the Cassandra database from the command line. All of the commands included in CQL are available on the CQLsh command line. The CQL command reference includes a synopsis, description, and examples of each CQL 3 command. These topics are covered in the following sections.