The FEDERATED storage engine is available beginning with MySQL 5.0.3. It is a storage engine that accesses data in tables of remote databases rather than in local tables.

The FEDERATED storage engine is available beginning with MySQL 5.0.3. This storage engine enables data to be accessed from a remote MySQL database on a local server without using replication or cluster technology. When using a FEDERATED table, queries on the local server are automatically executed on the remote (federated) tables. No data is stored on the local tables.

To include the FEDERATED storage engine if you build MySQL from source, invoke configure with the --with-federated-storage-engine option.

Beginning with MySQL 5.0.64, the FEDERATED storage engine is not enabled by default in the running server; to enable FEDERATED, you must start the MySQL server binary using the --federated option.

To examine the source for the FEDERATED engine, look in the sql directory of a source distribution for MySQL 5.0.3 or newer.

Additional Resources

MySQL Enterprise.  MySQL Enterprise subscribers will find MySQL Knowledge Base articles about the FEDERATED storage engine at FEDERATED Storage Engine. Access to the Knowledge Base collection of articles is one of the advantages of subscribing to MySQL Enterprise. For more information, see http://www.mysql.com/products/enterprise/advisors.html.