我有一个T-SQL查询，它显示来自表1的名为p1的Sum（TotalAmount）Sum（Discount）Sum（PayableAmount）和来自表2的名为p2的Sum（PaidAmount），
表p1和p2与Forenkay和主键没有任何关系，
所以我不能使用.net核心方法语法_context.Table1.include（a=〉a.table2）来连接两个表，因为这两个表之间没有关系，
因此，我已经将下面的代码编写为T-SQL查询，并获得了我想要的确切结果，但现在我想将相同的T-SQL查询编写为LING查询，并在我的C#.net核心控制器代码中将其用作查询语法或方法语法，
下面是我的T-SQL代码，它显示来自名为p1的表1的Sum（TotalAmount）Sum（Discount）Sum（PayableAmount），以及来自名为p2的表2的Sum（PaidAmount），

SELECT p1.PatientId, 
SUM(p1.TotalAmount) as TotalTreatmentAmount, 
SUM(p1.Discount) As TotalTreatmentDiscount,
SUM(p1.Payable) as TotalTreatmentPayable,
SUM(p1.Balance) as TotalTreatmentBalancce,
p2.TotalTreatmentPaidAmount
FROM PatientPayments as p1
join (SELECT p2.PatientId, SUM(p2.PaidAmount) as TotalTreatmentPaidAmount
FROM PatientPaymentHistories p2
where p2.PaymentType != 'Refund' 
group by p2.PatientId) as p2 
ON p2.PatientId = p1.PatientId
group by p1.PatientId, p2.TotalTreatmentPaidAmount

这是我的C#代码，但这段代码不工作，它的错误，只有SQL代码是工作正常

public IActionResult ExportPatientPaymentDataToExcel()
    {
        var PatientPayments =
        from p1 in _context.PatientPayments
        join p2 in _context.PatientPaymentHistories on p1.PatientId equals p2.PatientId
        select new
        {
            p1.PatientId,
            p1.TotalAmount,
            p1.Discount,
            p1.Payable,
            p2.PaidAmount
        };

        DataTable PatientPaymentTable = new DataTable("PatientPayment");
        PatientPaymentTable.Columns.AddRange(new DataColumn[5]
        {
              new DataColumn("Patient ID"),
              new DataColumn("Total Amount"),
              new DataColumn("Total Discount"),
              new DataColumn("Total Payable"),
              new DataColumn("Total Paid"),
        });

        foreach (var PatientPayment in PatientPayments)
        {
            PatientPaymentTable.Rows.Add(
            PatientPayment.PatientId,
            PatientPayment.TotalAmount,
            PatientPayment.Discount,
            PatientPayment.Payable,
            PatientPayment.PaidAmount

            );

        }
        using (XLWorkbook wb = new XLWorkbook())
        {
            wb.Worksheets.Add(PatientPaymentTable);
            using (MemoryStream stream = new MemoryStream())
            {
                wb.SaveAs(stream);
                return File(stream.ToArray(), "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet", GetLocalDateTime().Date.ToShortDateString() + "  " + "PatientPayment_Data.xlsx");
            }
        }

    }

请帮我把上面的T-SQL代码改成C#玲查询