CREATE FUNCTION
   ufDiscontinuedProductRowsInCategory(
   @CategoryID int)
RETURNS table
AS
RETURN(
   SELECT nc.CategoryID, nc.CategoryName,
      np.ProductName
   FROM Northwind.dbo.Categories AS nc,
      Northwind.dbo.Products AS np
   WHERE nc.CategoryID = np.CategoryID AND
      np.Discontinued = 1 AND
      np.CategoryID = @CategoryID)