How to start the project:

mvn clean install

To create the database, change the property 'spring.jpa.hibernate.ddl-auto' from validate to create and run the application.
(Don't forget to revert this before re-running the application. If you don't do this, you will delete all your inserted data.)

To insert test data, change the property 'spring.sql.init.mode' from never to always.
(Don't forget to revert this before re-running the application. If you don't do this, you will get duplicate data, or the script will fail
and as a result of this, the application won't start.)