CURRENT_TIME is limited to positive time in the range
from 00:00:00 to 23:59:59. So it should be enough 8 characters
to store it. However, it uses 10 characters in MariaDB-10.0.
For this script:
MariaDB 5.1 and 5.3 correctly returned length 8
(but wrong data type varbinary).
MariaDB 5.5 and 10.0 return wrong length (but correct data type varchar):
MySQL 5.5 and 5.6 return both type and length correctly: