Puzzling xml select синтаксис на сервере Sql

Question

В приведенном ниже коде sql, что означает T (C)? Что такое T и что такое C?

declare @employeeData xml --this would be your XML input parameter 
set @employeeData = '<employeeData> 
<employee LastName="Smith" FirstName="Randolph" EmployeeID="1234567"/> 
</employeeData>' 

declare @xmlTable table (LastName nvarchar(255), FirstName nvarchar(255), EmployeeID int) 

insert into @xmlTable (LastName, FirstName, EmployeeID) 
select 
C.value('@LastName','nvarchar(255)') as LastName, 
C.value('@FirstName','nvarchar(255)') as FirstName, 
C.value('@EmployeeID','int') as EmployeeID 
from 
@employeeData.nodes('/employeeData/employee') T(C) 

select * from @xmlTable 

Answer 1

Проверьте MSDN: http://msdn.microsoft.com/en-us/library/ms188282.aspx

T - Таблица C - Колонка