如何在LINQtoSQL中获取此信息？

为了让您了解一下上下文，我的数据库表如下所示：

用户
-用户ID
-名字

消息
-MessageID
-SenderUserID
-接收方用户ID

查看
-ViewID
-VieweeUserID
-ViewerUserID

使用一条LINQ to SQL语句，我希望获得所有“查看”或“发送消息”给用户的用户，并将其放入如下对象中：

互动者
-姓名（观众或留言者）
-NumberOfMessagesSent
-浏览次数

---

我已经尝试了很多年来得到我想要的，但每次我似乎得到疯狂的数据，所以我显然是做错了什么。。。请帮忙

模型上关系的名称可能会有所不同（这是LinqPad命名它们的方式），但我认为您正试图实现这一点：

Users.Select(u => new Interactor { 
                                   Name = u.Name, 
                                   NumberOfMessagesSent = u.SenderIdMessages.Count,
                                   NumberOfTimesViewed = u.ViewerIdViews.Count 
                                 })
     .Where(i => i.NumberOfMessagesSent > 0 || i.NumberOfTimesViewed > 0);

以及生成的SQL：

SELECT [t3].[Name], [t3].[value] AS [NumberOfMessagesSent], [t3].[value2] AS [NumberOfTimesViewed]
FROM (
    SELECT [t0].[Name], (
        SELECT COUNT(*)
        FROM [Message] AS [t1]
        WHERE [t1].[SenderId] = [t0].[UserId]
        ) AS [value], (
        SELECT COUNT(*)
        FROM [View] AS [t2]
        WHERE [t2].[ViewerId] = [t0].[UserId]
        ) AS [value2]
    FROM [User] AS [t0]
    ) AS [t3]
WHERE ([t3].[value] > @p0) OR ([t3].[value2] > @p1)

---

模型上关系的名称可能会有所不同（这是LinqPad命名它们的方式），但我认为您正试图实现以下目标：

Users.Select(u => new Interactor { 
                                   Name = u.Name, 
                                   NumberOfMessagesSent = u.SenderIdMessages.Count,
                                   NumberOfTimesViewed = u.ViewerIdViews.Count 
                                 })
     .Where(i => i.NumberOfMessagesSent > 0 || i.NumberOfTimesViewed > 0);

以及生成的SQL：

SELECT [t3].[Name], [t3].[value] AS [NumberOfMessagesSent], [t3].[value2] AS [NumberOfTimesViewed]
FROM (
    SELECT [t0].[Name], (
        SELECT COUNT(*)
        FROM [Message] AS [t1]
        WHERE [t1].[SenderId] = [t0].[UserId]
        ) AS [value], (
        SELECT COUNT(*)
        FROM [View] AS [t2]
        WHERE [t2].[ViewerId] = [t0].[UserId]
        ) AS [value2]
    FROM [User] AS [t0]
    ) AS [t3]
WHERE ([t3].[value] > @p0) OR ([t3].[value2] > @p1)

---

太好了，这很有帮助！我从完全错误的角度看它。我如何删除所有既没有查看也没有向用户发送消息的用户？太好了，这很有帮助！我从完全错误的角度看它。我如何删除所有既没有查看也没有向用户发送消息的用户？