14.3.1 Introduction to InnoDB 1.1 Features of the InnoDB Storage Engine InnoDB as the Default MySQL Storage Engine Checking InnoDB Availability Turning Off InnoDB Obtaining and Installing the InnoDB Storage Engine Viewing the InnoDB Storage Engine Version Number Compatibility Considerations for Downgrade and Backup InnoDB Storage Engine Change History Third-Party Software Contributions

InnoDB 1.1 combines the familiar reliability and performance of the InnoDB storage engine, with new performance and usability enhancements. InnoDB 1.1 includes all the features that were part of the InnoDB Plugin for MySQL 5.1, plus new features specific to MySQL 5.5 and higher.

Beginning with MySQL version 5.5, InnoDB is the default storage engine, rather than MyISAM. As of MySQL 5.5, issuing the CREATE TABLE statement without an ENGINE= clause creates an InnoDB table.

Key Advantages of InnoDB

Key advantages of InnoDB tables include:

To determine whether your server supports InnoDB use the SHOW ENGINES statement. See Section, “SHOW ENGINES Syntax”.

InnoDB Storage Engine Features

The InnoDB storage engine maintains its own buffer pool for caching data and indexes in main memory. When the innodb_file_per_table setting is enabled, each new InnoDB table and its associated indexes are stored in a separate file. When the innodb_file_per_table option is disabled, InnoDB stores all its tables and indexes in the single system tablespace, which may consist of several files (or raw disk partitions). InnoDB tables can handle large quantities of data, even on operating systems where file size is limited to 2GB.

InnoDB Enhancements and New Features

The InnoDB storage engine in MySQL 5.5 releases includes a number performance improvements that in MySQL 5.1 were only available by installing the InnoDB Plugin. This latest InnoDB (now known as InnoDB 1.1) offers new features, improved performance and scalability, enhanced reliability and new capabilities for flexibility and ease of use. Among the top features are Fast Index Creation, table and index compression, file format management, new INFORMATION_SCHEMA tables, capacity tuning, multiple background I/O threads, multiple buffer pools, and group commit. For more information about these features, see Section, “Features of the InnoDB Storage Engine”.

For additional information about InnoDB enhancements and new features in MySQL 5.5, also refer to:

Additional Resources