ODocument car = new ODocument(database, CAR);
car.field("plate", "JINF223S");
ODocument johnDoe = new ODocument(database, WORKER);
johnDoe.field("name", "John");
johnDoe.field("surname", "Doe");
johnDoe.field("car", car);
johnDoe.save();
johnDoeID = johnDoe.getIdentity().copy();
ODocument janeDoe = new ODocument(database, WORKER);