Using EnsLib.SQL.Service.GenericService to query local tables

I want to extract data from IRIS (Health Share Provider Directory) and write the data out to a file that I can use within an external system. Using EnsLib.SQL.Service.GenericService do I need to supply Credentials if I am querying IRIS locally? I have always used JDBC to connect externally when creating Services and Operations to read/write SQL data from external Databases, but never internally. Normally I would just use sql or code to pull the data within a Process or DTC. But in this case, I want the Service to drive the workflow, and query the data from Local Tables