相关疑难解决方法(0)

我设法让以下工作:

var transactions = from t in context.Transactions
                   group t.Create_Date_Time by t.Participation_Id
                       into t1
                   select new { ParticipationId = t1.Key, CreateDateTime = t1.Max() };

var cases = from c in context.Cases
            group c.Create_Date_Time by c.Participation_Id
                into c1
            select new { ParticipationId = c1.Key, CreateDateTime = c1.Max() };

var interactions = from i in context.Interactions
                   join pp in context.Party_Participation on i.Party_Id equals pp.Party_Id
                   group i.Last_Update_Date_Time.HasValue ? i.Last_Update_Date_Time : i.Create_Date_Time
                       by pp.Participation_Id
                       into i1
                   select new { ParticipationId = i1.Key, CreateDateTime = …