NOTE: The issue noted below is a good description of how SQL clients generally have issues with PUB schema namespace, but it is no longer (starting in April 2014) for using DDC with OpenEdge On-Premises databases. DDC now automatically defaults to the PUB schema, so you do NOT need to add the SET SCHEMA "pub" Initiatization String. The Default Schema is set to "pub" for new OpenEdge data sources.
I was playing with OpenEdge On-Premise Adapter from DataDirect Cloud and was running into the issue that I wanted to access pre-existing ABL OpenEdge Tables from JDBC. These are, of course, in the 'pub' schema namespace.
Note that you may also have to have the dba grant select privilege to the account you use for the JDBC connection. The default is that SQL users have no access rights to the tables in the PUB schema until they are explicitly granted.