LISTING 2: Recreate Subqueries as Self-Referencing Join

select  'MattressPrice' = Price, 'MattressMsrp' = Msrp, RailIDN,
	'RailPrice' = (select one.Price from Items one
	 inner join Items two on one.IDN = two.RailIDN and two.IDN = @IDN),
	'RailMsrp' = (select one.Msrp from Items one
	 inner join Items two on one.IDN = two.RailIDN and two.IDN = @IDN),
BoxspringIDN,
	'BoxspringPrice' = (select one.Price from Items one
	 inner join Items two on one.IDN = two.BoxspringIDN and two.IDN = @IDN),
	'BoxspringMsrp' = (select one.Msrp from Items one
	 inner join Items two on one.IDN = two.BoxspringIDN and two.IDN = @IDN),
'Name' = ItemName
from Items where IDN = @IDN