Hi

You can't use the getNextException() method, because it has to hard code in TOS which is not allowed.
Well, here are two workarounds.
NO.1: Check your database error log and find detail errors which cause Talend Job fail. There must something wrong with your data.
NO.2: Change TOS into Java Debug mode. Add breakpoint and see variables like 'ExceptionMessage' or 'detailMessage'.

Best regards!
Pedro