You can use the information provided here to know about padding, enabling / disabling it.
Traditionally, the JDBC Connector would pad data to be added in the CHAR datatype column if the length of data was less than the column width. This was the default behavior and there was no option for configuring the padding.
With the advent of the UTF-8 character set, this could result in unexpected behavior since the Connector was not able to determine the exact length of UTF-8 data. This, in turn, resulted in the adding of an indeterminate amount of whitespaces, and the data length became bigger than the column width which resulted in an exception thrown from the database.
To get around this problem we provide you with the option of optionally disable padding for various operations performed by the Connector, namely Insert, Update and Lookup operations, in AddOnly, Lookup, Update, Delete and Delta modes. See the Configuration section for the parameters selecting this functionality.
For UTF-8 data the padding should be disabled. For Latin-1 characters the padding can be enabled or disabled.