[ {emysql, [ {pool, 4}, {host, "localhost"}, {port, 3306}, {username, "root"}, {password, "root"}, {database, "emqtt"}, {encoding, utf8} ]}, {emqttd_plugin_mysql, [ {users_table, auth_user}, {acls_table, auth_acl}, {field_mapper, [ {username, username}, {password, password, pbkdf2}, {user_super, is_super_user}, {acl_username, username}, {acl_rw, rw}, {acl_topic, topic} ]} ]} ].