Method One
Generate a statement temporary file for the connection that needs to be processed through the connection information in the information_schema.processlist table, and then execute the instructions generated in the temporary file.

Method Two
Kill all current MySQL connections

Kill the connection run by the specified user, here is Mike

Method three
Implemented via SHEL script

Method Four
Through the mk-kill command provided in the Maatkit toolset

For more usage of mk-kill, please refer to:
http://www.maatkit.org/doc/mk-kill.html