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One of the benefits of Cassandra is the ability to develop using a number of different languages. Explore Cassandra support for JSON, user-defined functions, and Cassandra drivers for various development platforms.

Primary keys play a special role in Apache Cassandra. Not only are they used to uniquely identify a row in a table, they are also used to decide where and how data is stored in the underlying cluster. Begin by creating tables with different combinations of partitioning and clustering key columns, querying the tables, and confirming the keys were taking effect. Then, explore the exact semantics of queries on partition and clustering key columns. Finally, learn how to use the nodetool and grep utilities to view properties of partitions and to verify how rows are mapped to partitions on the basis of token ranges assigned to each partition. Upon completion, you will be able to contrast primary keys in Cassandra with those in other data technologies, differentiate between clustering and partition keys, and identify types of queries that are and are not allowed in Cassandra.

Apache Cassandra is a distributed NoSQL technology meant for large-scale data, so programmatic access to Cassandra is especially important. Cassandra supports client libraries in several major programming languages, like Java, Python, and C#. Developers use these to connect to Cassandra and to work with it from code. Begin by creating and using indexes in Cassandra. Then, define and invoke user-defined functions (UDFs) to perform aggregations. Finally, you'll create a Java Maven project with the datastax library as a dependency and connect to a Cassandra database using that library. You will create a Cassandra session, execute various operations using the datastax APIs, and confirm that these queries went through successfully. Upon completion, you will be able to create indexes on Cassandra tables, perform grouping and aggregation operations, leverage UDFs, and work programmatically with Cassandra from a Java client.