Defining Triggers and Sequences to populate identity columns in Oracle Database is no longer required. You have an Oracle Database 12c instance up and running, and you’re ready to hit the ground running.
Now How Do I Draw That Up in SQL Developer Data Modeler?
Draw your table. You’ll want a column.
RELATIONAL MODEL, COLUMN PROPERTIES
Ok, the Modeler now knows that this column is identifying, and that’s it’s going to be self-incrementing. Next we need to fill in the details.
MIN, MAX, INCREMENT BY, CACHE?
Last thing.
The modeler knows what you want to do with the column, but it doesn’t know what RDBMS features it has at its disposal. We need to go into the Physical Model level, ensuring we create a 12c physical model.
AFTER YOU’VE CREATED THE 12C PHYSICAL MODEL, GO TO THE TABLE, COLUMN AND ACCESS ITS PROPERTIES
YOU WANT THE ONE THAT SAYS ‘IDENTITY’ 
Here you go >>
THAT LOOKS RIGHT TO ME…
