InnoDB is the default storage engine for MySQL as of MySQL 5.5. 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.
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