The Statement.cancel() was made less susceptible to deadlocking, to allow application servers to immediately cancel operations that fail due to transaction timeouts or network issues. The abortInternal() method that was previously part of the MySQLConnection interface is now available through the Connection interface, so it can be tested for and called if available. (Bug #16224249)

When a statement was accessing a table in streaming mode, terminating the statement by issuing KILL QUERY from another session could cause a SQLException “Query execution was interrupted” and a stall when the original session issued a ResultSet.close() or Statement.close() method call. This issue resulted from a race condition and so could happen intermittently. (Bug #16198772, Bug #64204)

When the connection options noDatetimeStringSync and useTimezone were specified together, which is not allowed, the error message referred to an incorrect option name noDatetimeSync. (Bug #16061665, Bug #68011)

The connection.getQueryTimeoutKillsConnection() method could be called with a null parameter, causing NullPointerException errors and stack traces. The error depended on a race condition and so occurred intermittently. (Bug #13943631, Bug #64805)