Mybatis插入空值时，需要制定jdbcType

?jdbcType:

BIT?????????FLOAT??????CHAR???????????TIMESTAMP???????OTHER???????UNDEFINED

TINYINT?????REAL???????VARCHAR????????BINARY??????????BLOB????????NVARCHAR

SMALLINT????DOUBLE?????LONGVARCHAR????VARBINARY???????CLOB????????NCHAR

INTEGER?????NUMERIC????DATE???????????LONGVARBINARY???BOOLEAN?????NCLOB

BIGINT??????DECIMAL????TIME???????????NULL????????????CURSOR