I have a client prepared statement for query "select timestampadd(HOUR, ?, '2019-10-10')"
and set parameter as java Byte value '-6'.
In result, a mariadb 10.2.19 executes next query "select timestampadd(HOUR, 0xFA, '2019-10-10')"
Result of query is wrong because it has set wrong value for the parameter.
I've debugged it a bit and see that org.mariadb.jdbc.internal.com.send.parameters.ByteParameter.java uses hex for text protocol. It seems that code is wrong and should rather be similar to IntParameter.java class code.