What is "innodb"

InnoDB is a storage engine for MySQL. MySQL 5.5 and later use it by default. It provides the standard ACID-compliant transaction features, along with foreign key support ( Declarative Referential Integrity). It is included as standard in most binaries distributed by MySQL AB, the exception being some OEM versions.

InnoDB became a product of Oracle Corporation after its acquisition of Innobase Oy in October 2005. The software is dual licensed; it is distributed under the GNU General Public License, but can also be licensed to parties wishing to combine InnoDB in proprietary software.

MariaDB and Percona Server use a fork of InnoDB called XtraDB by default. XtraDB is maintained by Percona. Oracle InnoDB's changes are regularly imported into XtraDB, and some bug fixes and extra features are added.