The purpose of types

Now that you know the full range of types available in Cassandra, you may be wondering what purpose those types serve. In fact, the type system in Cassandra plays a few roles:

• Types are used for input validation. If you attempt to put a string value in an integer column, for instance, Cassandra will return an error.
• Type information is made available to client libraries; most adapters will return the results of queries with values represented using the appropriate data type for the language.
• In some scenarios, rows can be ordered by the value of a certain column. In that case, the type of the column determines the order of values in the column. For instance, in a text column, 2 is larger than 10, but in an int column, 10 is larger than 2.

You can find a full list of all the CQL data types in the DataStax CQL documentation at http://www.datastax.com/documentation/cql/3.1/cql/cql_reference/cql_data_types_c.html.

Now that we've got a firm grasp of how to create a Cassandra table and what options are available to us when creating columns, it's time to put the table to use.