Linq组由多个表和内部联接

Question

我有SQL查询，我想用linq重写它。这个sql命令只能连接两个表并在它们上面进行分组。问题在小组中。当我在一个表上使用group by时，一切正常，linq commant返回与sql命令相同的结果。但是当我想要连接两个表然后按H.Ucet（例如）分组时，它会返回其他结果作为我的sql命令。结果与使用左连接时相同，但我需要默认的内连接。

这是SQL命令：

string dotazBankUcty = @"SELECT 
H.UCET, 
SUM(H.MD) AS MD, 
SUM(H.DAL) AS DAL , 
SUM(H.MD_M) AS MD_M, 
SUM(H.DAL_ENA) DAL_M, 
MAX(UBUC.KOD) AS KOD 
FROM ACCOUNT H 
inner join UBU on H.UCET = UBU.UCET GROUP BY H.UCET"; 

我试图通过这个LINQ命令重写它。

var accountQuery = new XPQuery<ACCOUNT >(CoreHelper.DataSession); 

var ubuQuery = new XPQuery<UBU>(CoreHelper.DataSession); 

var resultBankyUcty = (from h in accountQuery 
    join u in ubuQuery on h.CompoundKey1.UCET equals u.UCET 
    group new { h, u } by new { h.CompoundKey1.UCET } into gUcty 
        select new 
        { 
        Ucet = gUcty.Key.UCET, 
        MD = gUcty.Sum(k => k.h.MD), 
        DAL = gUcty.Sum(k => k.h.DAL), 
        MD_M = gUcty.Sum(k => k.h.MDM), 
        DAL_M = gUcty.Sum(k => k.h.DALM), 
        KOD = gUcty.Max(k => k.u.KOD) 
        }); 

任何人都可以帮我吗？我看不到错误。

Answer 1

from t in (
      from h in accountquery 
      join u in ubuQuery on h.CompoundKey1.UCET equals u.UCET 
      select new {h,u} 
      ) group t by new {t.h.CompoundKey1.UCET} into g 

      select new { 
        Ucet = g.Key.UCET, 
        MD = g.Sum(k => k.h.MD), 
        DAL = g.Sum(k => k.h.DAL), 
        MD_M = g.Sum(k => k.h.MDM), 
        DAL_M = g.Sum(k => k.h.DALM), 
        KOD = g.Max(k => k.u.KOD) 
       };