VB.NET อยากได้ Code นับ/คำนวนค่าใน Data Acess อ่ะครับ ขอบคุณล่วงหน้าครับ

            var sumDetail = from sd in XElement.Load("c:\\detail.xml").Elements("Detail")
                            group sd by sd.Element("myDate").Value into sDetail
                            select new
                            {
                                InvoiceNo = sDetail.Key,
                                SumAmount = sDetail.Sum(x => Convert.ToDouble(x.Element("Amount").Value)),
                                SumDiscount = sDetail.Sum(x => Convert.ToDouble(x.Element("Discount").Value)),
                                SumBalance = sDetail.Sum(x => Convert.ToDouble(x.Element("Balance").Value)),
                                SumVat = sDetail.Sum(x => Convert.ToDouble(x.Element("Vat").Value))
                            };