if you want to run console app(part1) run the main class of "part1 module",
if you want to see one to one relationship between entities run main class of "part2(one to one)" module,
if you want to see one to many relationship between entities run main class of "part2(one to many)" module,
if you want to see many to many relationship between entities run main class of "part2(many to many)" module.