INSERT INTO [TESTDB].[dbo].[TestTable]
           ([TestValue]
           ,[TestValue2]
           ,[TestValue3]
           ,[TestValue4])
     VALUES
           ('01234'
           ,'56789'
           ,'98765'
           ,'43210')
GO
INSERT INTO [TESTDB].[dbo].[TestTable]
           ([TestValue]
           ,[TestValue2]
           ,[TestValue3]
           ,[TestValue4])
     VALUES
           ('01234'
           ,'98765'
           ,'56789'
           ,'43210')
GO
INSERT INTO [TESTDB].[dbo].[TestTable]
           ([TestValue]
           ,[TestValue2]
           ,[TestValue3]
           ,[TestValue4])
     VALUES
           ('01234'
           ,'43210'
           ,'56789'
           ,'98765')
GO
INSERT INTO [TESTDB].[dbo].[TestTable]
           ([TestValue]
           ,[TestValue2]
           ,[TestValue3]
           ,[TestValue4])
     VALUES
           ('01234'
           ,'98765'
           ,'43210'
           ,'56789')
GO


SELECT TOP 1000 [TestID]
      ,[TestValue]
      ,[TestValue2]
      ,[TestValue3]
      ,(SELECT TestValue + TestValue2 AS CompositeValue FROM [TESTDB].[dbo].TestTable AS foo WHERE foo.TestID=TestID)
  FROM [TESTDB].[dbo].[TestTable]</code>