2013-09-01 118 views
2

Guy's我需要此sql语句的Lambda表达式。将sql转换为Lambda表达式

select GalleryId, Max(Bid) 
from BidModels 
where GalleryId in (select GalleryId from BidModels where UserId = (UserId)) 
group by GalleryId 
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userid = userid是一个no-op(总是为true)。你是否打算将其中的一个作为输入参数? – Hogan

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对不起,用户ID是变量应该是用户ID =一些PARR? –

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你确定你的意思是lambda或是LINQToSQL? – Nilesh

回答

0

这里是你如何能做到这

var galleryIds = (bidModelses.Where(b => b.UserId == [YOURPARAMETER]) 
       .Select(b => b.GalleryId)); 

var query = (bidModelses.Where(bm => galleryIds.Contains(bm.GalleryId)) 
      .GroupBy(bm => bm.GalleryId) 
      .Select(gbm => new {gbm.Key, MaxBid = gbm.Max(p => p.BidId)})); 
1

我不明白为什么你需要的子查询,因为你可以选择其中传递用户ID =用户ID的所有投标;与记:

var userid = <whatever>; 

var query = from b in BidModels 
      where b.UserId = userid 
      group by b.GalleryId into g 
      select new {Id = g.Key, MaxBid = g.Max(x => x.Bid)}; 
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我正在尝试查询数据库,以查找特定于与所有用户的出价相关的用户的出价出价。换句话说,我希望一个投标人知道他的出价与他的同一套产品的其他出价有关。 –

0

这似乎是答案感谢您的帮助:

from b in BidModels 
let MyGallery = from a in BidModels where a.UserId == (1) select new { a.GalleryId } 
where MyGallery.Any() 
group b.Bid by b.GalleryId into g 
select new 
{ Id  = g.Key, 
    MaxBid = g.Max() 
}