关于linq的两个有关问题

关于linq的两个问题
通过linq查询出如下结果，

实现的语句为：

var result1 = from a in t.T_BaseBookInfo
                              join b in t.T_BorrowInfoHsty  //表
                              on a.GUID equals b.BookID
                              join c in t.T_BaseBookInfo   //表
                              on b.BookID equals c.GUID
                              join d in t.T_Press 
                              on c.PressCode equals d.PressCode
                              select new BorrowRankingModel   //BorrowRankingModel 为自建模型
                              {
                                  GUID = b.BookID,
                                  PressName=d.PressName,
                                  Author=c.Author,
                                  BookTitle=c.BookTitle
                              };

我想根据最后一列绑定的字段（字段为“GUID”）分组，把guid相同的合并成一条，“流通次数”那列中放入条数，并从大到小排列，在第一列写入1,2,3,4……序号（这个序号的问题我发现用个 ++ 的方法不行这个方法我行不通）
linq 合并
[解决办法]
以为你的是LINQ2SQL， LINQ2EF不支持SELECT的重载方法，可以这样：

var result1 = (from a in t.T_BaseBookInfo
                              join b in t.T_BorrowInfoHsty  //表
                              on a.GUID equals b.BookID
                              join c in t.T_BaseBookInfo   //表
                              on b.BookID equals c.GUID
                              join d in t.T_Press 
                              on c.PressCode equals d.PressCode 
                              select new BorrowRankingModel  
                              {
                                  GUID = b.BookID,

                                  PressName=d.PressName,
                                  Author=c.Author,
                                  BookTitle=c.BookTitle
                              }).AsEnumberable().GroupBy(x=>x.GUID)
                             .Select((g,i)=> new BorrowRankingModel  
                              {
                                  排名=i+1,
                                  GUID = g.Key,
                                  流通次数=g.Count(),
                                  PressName=g.First().PressName,
                                  Author=g.First().Author,
                                  BookTitle=g.First().BookTitle
                              };

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