C# EF查询创建大量子查询

我有以下数据结构：

会议

有一对多的

会议室

会议室

有一对多的

会议

这些数据通过联接表进行关联：

public class MeetingRoomMeeting : Entity
    {
        public Guid MeetingRoomId { get; set; }
        public virtual MeetingRoom MeetingRoom { get; set; }

        public Guid MeetingId { get; set; }
        public virtual Meeting Meeting { get; set; }
    }

会议也有与会者，其定义如下：

一次

会议

有一对多的

与会者

与会者

有1个

会议

我有两个问题：

获取

会议室的所有
会议
，以及

获取
会议室中所有
会议的平均
与会者

查询执行时间的差异大约为100-200秒（仅获取一个房间的会议），以及约30-50秒（获取与会者）

查询如下:

这将返回会议列表（用于进一步聚合和转换）。它是在一组日期之间为特定房间（由其Guid定义）举行的会议

var meetings = _reader.Query()
               .Where(room => room.Id == query.Id)
               .Include(room => room.Meetings)
                   .ThenInclude(meeting => meeting.Meeting)
               .Select(room => new Models.MeetingRoom
               {
               Id = room.Id,
               Name = room.Name,
               Location    = room.Location,
               Meetings = room.Meetings.Where(meeting => meeting.Meeting.StartTime >= query.StartTime && meeting.Meeting.EndTime <= query.EndTime).Select(meeting => new MeetingRoomMeeting
                   {
                       MeetingId = meeting.MeetingId,
                       Meeting = meeting.Meeting
                   }).ToList()
               })
           .FirstOrDefault();

然后是一吨这些：

SELECT [a].[Id], [a].[Internal], [a].[MeetingId], [a].[PersonId], [a].[Rating], [a].[WasOrganizer]
FROM [Attendee] AS [a]

我确信我在构造LINQ查询时做了一些非常不允许的事情。我考虑在与会者上添加MeetingRoom.Id，以便能够使用
MeetingRoom.Id内部加入Attendee.MeetingRoom\u Id
尝试包含
meeting.meeting.Attenders
。看来你的atendees是懒散加载的。不幸的是，它似乎不起作用。尝试了.Include（room=>room.Meetings）。然后尝试了Include（meeting=>meting.meeting.attendes）和[…]。然后尝试了Include（meeting=>meeting.Meetings）。然后尝试了Include（meeting=>meeting.attendes）-仍然会在我的档案器中进行查询。也可以尝试Include
meeting.meeting.attendes
。看来你的atendees是懒散加载的。不幸的是，它似乎不起作用。尝试了.Include（room=>room.Meetings）。然后Include（meeting=>meting.meeting.attendes）和[…]。然后Include（meeting=>meeting.meeting）。然后Include（meeting=>meeting.attendes）-仍然在我的档案器中进行查询。
    var meetings = _reader.Query()
                .Where(room => room.Id == query.Id)
                .Include(room => room.Meetings)
                    .ThenInclude(meeting => meeting.Meeting)
                .Select(room => new Models.MeetingRoom
                {
                    Id = room.Id,
                    Name = room.Name,
                    Location = room.Location,
                    Meetings = room.Meetings.Where(meeting => meeting.Meeting.StartTime >= query.StartTime && meeting.Meeting.EndTime <= query.EndTime).Select(meeting => new MeetingRoomMeeting
                    {
                        MeetingId = meeting.MeetingId,
                        Meeting = new Models.Meeting
                        {
                            StartTime = meeting.Meeting.StartTime,
                            Attendees = meeting.Meeting.Attendees
                        } 
                    }).ToList()
                })
                .FirstOrDefault();

N'SELECT [meeting].[MeetingRoomId], [meeting].[MeetingId], [meeting.Meeting].[StartTime], [meeting.Meeting0].[Id]
FROM [MeetingRoomMeeting] AS [meeting]
INNER JOIN [Meeting] AS [meeting.Meeting] ON [meeting].[MeetingId] = [meeting.Meeting].[Id]
INNER JOIN [Meeting] AS [meeting.Meeting0] ON [meeting].[MeetingId] = [meeting.Meeting0].[Id]
WHERE ([meeting.Meeting].[StartTime] >= @__query_StartTime_1) AND ([meeting.Meeting].[EndTime] <= @__query_EndTime_2)',N'@__query_StartTime_1 datetime2(7),@__query_EndTime_2 datetime2(7)',@__query_StartTime_1='2016-10-02 22:00:00',@__query_EndTime_2='2016-11-03 22:59:59'

SELECT [a].[Id], [a].[Internal], [a].[MeetingId], [a].[PersonId], [a].[Rating], [a].[WasOrganizer]
FROM [Attendee] AS [a]