Question

I have the query:

var q = 
    (
        from c in db.tblArcadeGamePlays 
        join a in db.tblProfiles on c.UserID equals a.UserID
        where c.UserID != 0
        orderby c.Date descending
        select new { c.UserID, c.tblForumAuthor.Username, a.EmailAddress }
    )
    .Distinct()
    .Take(12);   

This takes the correct records, but isn’t ordering them. If I switch the orderby to asc/desc it has no affect! Can anyone point out what I can do to return the records newest first?

Edit

It’s returning the correct ordering of results if the Distinct() is removed, but it’s now returning the same user record over and over again (I only want each user to appear once)

Answer 1

It sounds like you want the distinct list to be ordered by the newest item in each set, right?

To do this, you should use a group by. You’ll have to order twice, once within each set, and once again for the entire list:

var q = 
    from s in 
    (
        from c in db.tblArcadeGamePlays 
        join a in db.tblProfiles on c.UserID equals a.UserID
        where c.UserID != 0
        select new { c.UserId, c.TblForumAuthor.Username, a.EmailAddress, c.Date }
    )
    group s by new { g.UserId, g.Username, g.EmailAddress } into g
    orderby g.OrderByDescending(s => s.Date).First().Date descending
    select g.Key
    )
    .Take(12);  

The orderby part might look confusing, but it’s simply: order the groups by the first date within each group