The FEDERATEDX and CONNECT storage engines

The FEDERATEDX and CONNECT storage engines allow us to use a remote table as if it were located in the local server. Local FEDERATEDX and CONNECT tables act as a proxy between the client and the remote server. When the client sends a SQL statement to the tables, the tables send it to the remote server; when the remote server returns some results, the tables send the result to the client.

This is not the most advanced solution to share data between multiple servers. The SPIDER storage engine has more features and optimizations, as explained in the next section. However, FEDERATEDX and CONNECT may have some advantages.

MariaDB Knowledge Base explains that the initial version of FEDERATEDX has been developed for Cisco. Its devices did not have much storage space, so they needed a MySQL storage engine to access remote data. This engine at the time was called FEDERATED, and was included in MySQL 5.0. More features were added in MySQL 5.1 to make it...