linq query with MyModel

I have an object model and I'm looking to populate it with a linq query.

MyModel{
DateTime AppointDate {get; set;}
int TotalAppoints {get; set;}
int AppointDuration {get; set;}
}

The query I'm writing is returning the count of appointments for a specific date and is in a function that receives the UserID and the date as parameters. MyDC is the data context.

So far, this is what I have:

var Output = from a in MyDC.App开发者_运维知识库ointTable
             where a.UserID == TheUserID
             where a.Date == TheDate.Date
             select new MyModel
             {
                AppointDate = ?,

                TotalAppoints =?,

                AppointDuration = ?
             };

For now, I've tried a few things but it's not returning what's expected. When I write a.Count() I'm not getting the count. Each appointment has an int that stores the number of minutes for that appointment; TotalAppoints is supposed to be the count of appointments and AppointDuration is supposed to hold the count of all the minutes spent in appointments. Thanks for your input.

---

What you want to do is group your data by that field and sum across the values

var out = from a in MyDC.AppointTable
            where a.UserID == TheUserID
            where a.Date == TheDate.Date
            group a by a.Date into g
            select new MyModel {
               AppointDate = TheDate.Date,
               TotalAppoints = g.Count(),
               AppointDuration = g.sum( x => x.AppointDuration )
            };