MySQL is an open source relational database management system (RDBMS) that can be acquired directly from Mysql.com, Oracle Software Delivery Cloud, or from the MySQL github repository.
MySQL offers a pluggable storage engine architecture that enables different storage engines to be loaded and unloaded from a running MySQL server. Each storage engine can suit the needs of a different use case. Documentation on the supported storage engines can be found in the MySQL Reference Manual: Alternative Storage Engines.
Due to its open source nature, there are a number of MySQL forks and deployment types. Some deployment types and revisions are:
- MySQL Community Edition - Freely downloadable and available under the GPL license. Includes multiple storage engines and is supported by a community of open source developers.
- MySQL Enterprise Edition - A commercial version of MySQL which Includes a comprehensive set of advanced features and management tools.
- MySQL Classic Edition - A commercial version of MySQL with standard database capabilities. Includes the InnoDB and MyISAM storage engines.
- MySQL Cluster - A commercial version of MySQL as a distributed database providing scalability and high availability. Uses the NDB storage engine.
- MySQL InnoDB Cluster - A high availability solution for MySQL where data is replicated between MySQL server instances.