Can you show me how many restaurant is the sandwich type restaurant?
SELECT count ( * )  FROM Restaurant JOIN Type_Of_Restaurant ON Restaurant.ResID  =  Type_Of_Restaurant.ResID JOIN Restaurant_Type ON Type_Of_Restaurant.ResTypeID  =  Restaurant_Type.ResTypeID GROUP BY Type_Of_Restaurant.ResTypeID HAVING Restaurant_Type.ResTypeName  =  'Sandwich'
count of restaurants = COUNT(*); restaurant type refers to Restaurant_Type.ResTypeName; 'Sandwich' type restaurant refers to Restaurant_Type.ResTypeName = 'Sandwich';