Cannot generate Oracle DDL for Entity using Identity Key Generator

When trying to generate DDL for my entity model the following error prompt and complain identity key generator is not supported.

Generate DDL for Oracle complain identity key generator is not supported

This problem is caused by the database connection in your project was specified to use the old Oracle dialect. To solve this problem:

1. Go to Tools > DB > Database Configuration…
   

   Open database configuration dialog

2. Press the green down arrow button next to Driver field.
   

   Open database configuration dialog

3. Select org.hibernate.dailect.Oracle12cDialect.
   

   Select Oracle 12c Dialect

4. Press OK to confirm the change.

Now you will able to generate DDL for your entity with primary key specified to use identity as key generator.

Primary key with identity key generated being able to generate to DDL