使用join，group-by和where將sql轉換為linq

Question

我有以下sql，我想轉換為linq

SELECT Contrato.finca, SUM(Pago.Importe_subtotal)
FROM Pago, Contrato
WHERE Pago.Contrato = Contrato.ID AND Pago.pagado = 1
GROUP BY Contrato.finca
ORDER BY 2 DESC
GO

我現在在linq中有以下內容，但是group by不起作用。

var x = from contrato in ctx.Contratos 
        join pago in ctx.Pagos
        on contrato.ID equals pago.Contrato 
        where pago.pagado == true 
        group contrato by contrato.finca
        select contrato.Finca1;

Answer 1

認為這應該工作：

ctx.Pagos.Where(m=>m.pagado==true).GroupBy(m=>m.Contrato.finca) 
    .Select(m=> new { Id= m.Key, Val= m.Sum(n => n.Importe_subtotal)})

Answer 2

嘗試

var x = from contrato in ctx.Contratos 
        join pago in ctx.Pagos
        on contrato.ID equals pago.Contrato 
        where pago.pagado == true 
        group new {contrato, pago} by contrato.finca into g
        select new {
            key = g.Key, 
            sum = g.Sum(p => p.pago.Importe_subtotal)
        };