I don't use Oracle, but based on the MS SQL Server setup, I would guess that the user you define to connect to the Oracle database needs to the the owner of the schema
Edit:
Again, emphasising that I do not use Oracle... the short answer would be full rights to the schema. So something like
grant alter session, create cluster, create database link, create sequence, create session, create synonym, create table, create view, create procedures, create trigger, query rewrite to ...
To run your application with an oracle database, you need to set in your project settings --> Configurations --> New --> Database type as oracle. I have been working with oracle in this way. Security rights are not required to configure oracle with your project or any application.