May 03, 2011 10:31 PM|Decker Dong - MSFT|LINK
As far as I know, the auto increament Id should be done with numeric type (like int or Long). As for a string type, I'm afraid you cannot do that in SQL directly.
However, if you want to show it, you can do!
if you want to show Employees' Ids onto the GridView, Just do this in the <ItemTemplate>——
and the other is——