Apache Cassandra is a distributed open source key-value NoSQL DBMS . Initially developed by Facebook, the application was later published as an open source project. A free integrated distribution of Apache Cassandra – DataStax Community Edition – and a commercial edition of Apache Cassandra are also available on DataStax.
Apache Cassandra was created for online applications requiring fast performance with no downtime. This key-value database system excels when most, if not all, accesses look for data based on a primary key value. It has been designed to handle very large volumes of data distributed on basic servers, with high availability and no point of failure.
Available for Linux, Windows and Mac OS X operating systems, Apache Cassandra is open source software for free download .
Features of Apache Cassandra
The latest version of Apache Cassandra, 2.1.6, offers several improvements regarding stability and a number of bugfixes. The download and installation of the package configure Apache Cassandra for execution on a single node. Although this configuration is supported, Apache Cassandra is more often run as a multinoeud cluster , which requires additional configuration that Cassandra configuration files allow.
DataStax Enterprise , the enterprise version of Apache Cassandra, leverages Cassandra and provides additional features such as search, analytics, and performance. DataStax Enterprise, like Apache Cassandra, is designed for online applications that require high speed and availability, but also offers enterprise development and management capabilities.
Apache Cassandra Licenses
Subscriptions to DataStax Enterprise are open to production and non-production environments. Both include certified software and DataStax support.
DataStax Enterprise can be used for free in development environments. Running the product requires the purchase of a license or registration in the startup program.
The DataStax Start-up program is open to startups with less than $ 2 million in annual profits and less than $ 20 million in fundraising. It allows you to use DataStax Enterprise for free and unlimited. The number of nodes is not limited and there are no hidden restrictions. DataStax support services include 24/7/365 service level agreements, certified service packs that continuously update the software, and patch support for emergency maintenance.
DataStax is not the only business support option for Apache Cassandra: other companies provide support services.
Apache Cassandra Data Types
The NoSQL Apache Cassandra DBMS supports the most common data types: ASCII, bigint, BLOB, Boolean values, counter data, decimal, double, floating point, int, text, timestamp, UUID, VARCHAR, and varint.
Cassandra’s data model provides columnar indexes, structured updates to logs, enhanced support for denormalization views and materialized views, and integrated caching.
Data access is achieved using the Cassandra Query Language (CQL) query language, which is close to SQL.
Apache Cassandra Performance Evaluation Tests
Engineers at the University of Toronto conducted performance tests in 2012 on NoSQL database engines. Their findings indicate that “Cassandra’s throughput dominates in all tests, but its latency is particularly high in all these tests.”