// Saves product and returns its id (guid) public Product Add(ProductCreateInputModel model) { if (model.IsValid()) { Product p = new Product() { Id = GetNewGuid().ToString(), Name = model.Name, Price = model.Price }; string sql = $@"INSERT INTO {productTableName} VALUES ('{p.Id}', '{p.Name}', {p.Price.ToString(cultureInfo)});"; _databaseAccess.Execute(sql); return(p); } return(null); }