using (var northwind = new NorthwindModel.NorthwindEntities()) {
DateTime today = DateTime.Now;

var ordersToShip =
from o in northwind.Orders
where o.RequiredDate <= today
	&& o.ShippedDate == null
select o;

foreach (var o in ordersToShip) {
	o.ShippedDate = today;
}

using (TransactionScope scope = new TransactionScope()){
northwind.SaveChanges();
scope.Complete();
}
}
