This is a very common question. There will probably be a cover charge, this is for the table cloth 'covering' the table and cutlery or a 'service' charge for the service provided by the staff, check on the menu or with your waiter if this included or not. If it isn't then the amount will be between 12 and 15% of the total bill. In this case it isn't necessary to tip as the locals are notoriously bad tippers and just pay the service charge. Or, just leave the change if it's a couple of euros and the service has been good.