T-SQL create a simple pivot table

pivotExample.sql

CREATE TABLE OrderItem(
	lineItemId int IDENTITY(1,1) NOT NULL,
	orderid int NOT NULL,
	itemName nchar(10) NOT NULL,
	qty int NOT NULL
) 
GO

INSERT INTO OrderItem (orderid,itemName,qty)
     VALUES (100, 'ipad', 4),
			 ( 100, 'iphone', 2),
			 ( 100, 'ipod', 10),
			 ( 200, 'ipad', 4),
			 ( 200, 'iphone', 2),
			 ( 300, 'ipod', 10),
			 ( 400, 'ipad', 4),
			 ( 400, 'iphone', 2),
			 ( 500, 'ipod', 10)
GO

--Show the result in vertical way
select itemName, sum(qty) from orderitem group by itemName

--This is a home-made "pivot". The next one will be using the pivot function.
--Show the result in horizontal way
select sum(ipadQty) as ipadQty, sum(iphoneQty) as iphoneQty, sum(ipodQty) ipodQty
from
(
	select 
		ipadQty=case when itemName='ipad' then qty else 0 end,
		iphoneQty=case when itemName='iphone' then qty else 0 end,
		ipodQty=case when itemName='ipod' then qty else 0 end
	from
		(select itemName, sum(qty) as qty from orderitem group by itemName) as vertical
) unmerged

--Using pivot function to get the total qty for each product
select [ipad] as  ipadTotalQty, [iphone] as iphoneTotalQty, [ipod] as ipodTotalQty from
(select itemname, qty from orderitem ) as sourcetable
pivot
(
	sum(qty) for itemname in ([ipad] ,[iphone] ,[ipod])
) as pivotTable

--Using pivot function to get the total qty for each order
select  [100] as  order100Qty, [200] as order200Qty, [300] as order300Qty, [400] as order400Qty, [500] as order500Qty from
(select orderid, qty from orderitem ) as sourcetable
pivot
(
	sum(qty) for orderid in ([100],[200],[300],[400],[500])
) as pivotTable

--Using pivot function to get the total qty for each product, grouped by orders
select orderid, [ipad] as  ipadTotalQty, [iphone] as iphoneTotalQty, [ipod] as ipodTotalQty from
(select orderid, itemname, qty from orderitem ) as sourcetable
pivot
(
	sum(qty) for itemname in ([ipad],[iphone],[ipod])
) as pivotTable