linq group by sum and join example

var fees =
            from p in i.AccountFees

            group p by p.FeeID into g
            select new { FeeID = g.Key, TotalAmount = g.Sum(p => p.Amount) };

            foreach (var fee in fees) {
                Logger.prn("" + fee.FeeID + ":" + fee.TotalAmount);
            }

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