MySQL 5.7 Release Notes
DROP SERVER [ IF EXISTS ] server_name
Drops the server definition for the server named
corresponding row in the
mysql.servers table is
deleted. This statement requires the
Dropping a server for a table does not affect any
FEDERATED tables that used this connection
information when they were created. See
Section 13.1.17, “CREATE SERVER Statement”.
DROP SERVER causes an implicit commit. See
Section 13.3.3, “Statements That Cause an Implicit Commit”.
DROP SERVER is not written to the binary log,
regardless of the logging format that is in use.