I have done some searching and although there are reports of issues with preferences I have not found this one.
I am using SDDM 17.4.0.335 on Mac OS 10.13.3.
Upon opening Data Modeler, I select Preferences -> Data Modeler -> Model
I then select "Oracle Database 12c" as the "Default RDBMS Type" and then click on "OK".
I then select Preferences -> Data Modeler -> Model and the "Default RDBMS Type" is set to "Oracle Database 11g".
How to I get preferences to stick?
Thank you.