// 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);
        }