"SQL Exception reading Object" error for Netezza nzjdbc.jar

Hello and thanks in advance.  I have KNIME 3.4.1 on Windows.

I'm very new to KNIME, but have successfully set up my Netezza driver in the Database Preferences section (via pointing to the nzjdbc.jar file).  I've also successfully connected to my Netezza SQL database and can retrieve some queries without issue.

In some cases, I get the following error on the 'Database Table Connector' > 'Database Connection Table Reader' node setup:

ERROR Database Connection Table Reader      SQL Exception reading Object of type "-9": netezza.feature.not.supported - all further errors are suppressed and reported on debug level only

I believe I've narrowed the issue to certain fields that are setup as VARCHARS or other String types, but don't see a particular pattern.  Is there any other node setup that would get around this?  Thanks!


this seems to be a problem when trying to read NVARCHAR (SQLType=-9) columns from Netezza. KNIME uses the ResultSet.getNString() method to read these columns but this seems to fail for Netezza or the used driver. Maybe you can try to convert the type of the column in the database or on the fly by casting the Column in a DB Query node.