MySQL 5.7 has fractional seconds support for TIME, DATETIME, and TIMESTAMP values, with up to microseconds (6 digits) precision.

mysql> CREATE TABLE fractest( c1 *TIME(2)*, c2 *DATETIME(2),* c3 *TIMESTAMP(2)* );
mysql> INSERT INTO fractest VALUES ('17:51:04.777', '2014-09-08 17:51:04.777', '2014-09-08 17:51:04.777');

Now the millisecond part is ignore, hope the connector can support this new feature

UPDATE: Upon closer inspection, the container was not properly reconstructing temporal values and encoding them in Kafka Connect records.