FEDERATED Storage Engine
The FEDERATED Storage Engine is a legacy storage engine no longer being supported. A fork, FederatedX is being actively maintained. Since MariaDB 10.0, the CONNECT storage engine also permits accessing a remote database via MySQL or ODBC connection (table types: MYSQL, ODBC).
The FEDERATED Storage Engine was originally designed to let one access data remotely without using clustering or replication, and perform local queries that automatically access the remote data.