Going out for diner means people will gather at the restaurant around 8 or 8:30 pm. On week-ends it can even be around 9 or 9:30 pm.
After diner, friends will go to a bar or a pub, to have some drinks and chat. Only after midnight or around 1 am they’ll go to disco.
So, don’t expect to see and enjoy the local nightlife if you have diner at 7 pm and want to have fun at 9 or 10 pm. There will be nobody around.