MySQL 5.5.25

MySQL Community Edition is a freely downloadable version of the world's most popular open source database that is supported by an active community of open source developers and enthusiasts.

MySQL delivers enterprise features, including:

Partitioning to improve performance and management of very large database environmentsRow-based/Hybrid Replication for improved replication securityEvent Scheduler to create and schedule jobs that perform various database tasksXPath SupportDynamic General/Slow Query LogPerformance/Load Testing Utility (mysqlslap)Improved! Full Text Search (faster, new dev templates)Improved! Archive engine (better compression, more features)Improved! User session and problem SQL identificationImproved! MySQL embedded library (libmysqld)Additional INFORMATION_SCHEMA objectsFaster data import operations (parallel file load)ACID Transactions to build reliable and secure business critical applicationsStored Procedures to improve developer productivityTriggers to enforce complex business rules at the database levelViews to ensure sensitive information is not compromisedInformation Schema to provide easy access to metadataPluggable Storage Engine Architecture for maximum flexibilityArchive Storage Engine for historical and audit data

Download here