A good(elegant) way to retrieve records with counts - linq-to-sql

Question

Context: ASP.NET MVC 2.0, C#, SQL Server 2008, IIS7
I have 'scheduledMeetings' table in the database.
There is a one-to-many relationship: scheduledMeeting -> meetingRegistration
So that you could have 10 people registered for a meeting.
meetingRegistration has fields Name, and Gender (for example).
I have a "calendar view" on my site that shows all coming events, as well as gender count for each event.
At the moment I use Linq to Sql to pull the data:
var meetings = db.Meetings.Select(
m => new {
MeetingId = m.Id,
Girls = m.Registrations.Count(r => r.Gender == 0),
Boys = m.Registrations.Count(r=>r.Gender == 1)
});
(actual query is half-a-page long)
Because there is anonymous type use going on I cant extract it into a method (since I have several different flavors of calendar view, with different information on each, and I don't want to create new class for each).
Any suggestions on how to improve this?
Is database view is the answer?
Or should I go ahead and create named-type?
Any feedback/suggestions are welcome. My DataLayer is huge, I want to trim it, just don't know how.
Pointers to a good reading would be good too.

Answer 1

I'd extend your Meetings class by adding 2 properties:
public partial class Meeting
{
#region Properties
public int BoyCount { get; set; }
public int GirlCount { get; set; }
#endregion
}
With deferred loading:
var items = db.Meetings.Select(
m => new {
Meeting = m,
Girls = m.Registrations.Count(r => r.Gender == 0),
Boys = m.Registrations.Count(r = >r.Gender == 1)
}).ToList();
items.ForEach(i =>
{
i.Meeting.BoyCount = i.Boys;
i.Meeting.GirlCount = i.Girl;
});
List<Meeting> = items
.Select(i => i.Meeting)
.ToList();
With eager loading, one of the solutions is to load Registrations with your Meeting entity:
DataLoadOptions loadOptions = new DataLoadOptions();
loadOptions.LoadWith<Meeting>(m = > m.Registrations);
db.LoadOptions = loadOptions;
In this case the partial class properties above are became getters:
public partial class Meeting
{
#region Properties
public int BoyCount
{
get
{
return this.Registrations
.Count(r => r.Gender == 1);
}
}
public int GirlCount
{
get
{
return this.Registrations
.Count(r = > r.Gender == 0);
}
}
#endregion
}