Linq to sql 在子查询中分组的Linq外部联接

Linq to sql 在子查询中分组的Linq外部联接,linq-to-sql,Linq To Sql,我需要将Linq中的以下相关子查询转换为Sql。我能够实现左外连接部分。然而,在子查询中分组是我得到错误结果的地方 SELECT ae.Id,ae.Title ,(select COUNT(*) from [dbo].[AssociationEventRSVP] where RSVPStatus='Y' group by AssociationEventId, RSVPStatus having RSVPStatus='Y' and AssociationEventId=ar.As

我需要将Linq中的以下相关子查询转换为Sql。我能够实现左外连接部分。然而,在子查询中分组是我得到错误结果的地方

SELECT 
  ae.Id,ae.Title
,(select COUNT(*) from [dbo].[AssociationEventRSVP]  where RSVPStatus='Y'
 group by  AssociationEventId, RSVPStatus having RSVPStatus='Y'
 and AssociationEventId=ar.AssociationEventId) as CountYes
,(select COUNT(*) from [dbo].[AssociationEventRSVP]  
 group by  AssociationEventId, RSVPStatus having RSVPStatus='N'
 and AssociationEventId=ar.AssociationEventId) as CountNo 
  FROM [dbo].[AssociationEvents] as ae
  left outer join AssociationEventRSVP as ar
  on ae.Id=ar.AssociationEventId
提前感谢你的帮助


Tushar M.

我首先将您的查询重构为:

SELECT 
ae.Id,
ae.Title,
(select COUNT(*) FROM [dbo].[AssociationEventRSVP] WHERE RSVPStatus='Y' AND AssociationEventId=ae.Id) AS CountYes,
(select COUNT(*) FROM [dbo].[AssociationEventRSVP] WHERE RSVPStatus='N' AND AssociationEventId=ae.Id) AS CountNo 
FROM [dbo].[AssociationEvents] as ae
var results = from ae in context.AssociationEvents
              select new
              {
                  ae.Id,
                  ae.Title,
                  CountYes = context.AssociationEventRSVP.Where(aer => aer.RSVPStatus == "Y" && aer.AssociationEventId == ae.Id).Count(),
                  CountNo  = context.AssociationEventRSVP.Where(aer => aer.RSVPStatus == "N" && aer.AssociationEventId == ae.Id).Count()
              };
这里有一个简单(不一定高效)的LINQ到SQL转换:

SELECT 
ae.Id,
ae.Title,
(select COUNT(*) FROM [dbo].[AssociationEventRSVP] WHERE RSVPStatus='Y' AND AssociationEventId=ae.Id) AS CountYes,
(select COUNT(*) FROM [dbo].[AssociationEventRSVP] WHERE RSVPStatus='N' AND AssociationEventId=ae.Id) AS CountNo 
FROM [dbo].[AssociationEvents] as ae
var results = from ae in context.AssociationEvents
              select new
              {
                  ae.Id,
                  ae.Title,
                  CountYes = context.AssociationEventRSVP.Where(aer => aer.RSVPStatus == "Y" && aer.AssociationEventId == ae.Id).Count(),
                  CountNo  = context.AssociationEventRSVP.Where(aer => aer.RSVPStatus == "N" && aer.AssociationEventId == ae.Id).Count()
              };