LINQ Lambda Left join with an Inner join

Question

I have written a LINQ lambda query which so far which returns all staff which do not have an associated training row which works fine. I now need to amend my where clause to use

Answer 1

Inner joins are performed with the Join method. I think your query should go something like this:

var query = db.staff
              .GroupJoin(db.training,
                         s => s.id,
                         t => t.staff_id,
                         (s, t) => new { Staff = s, Training = t.FirstOrDefault() })
              .Join(db.manager,
                    gj => gj.Staff.manager_id,
                    m => m.id,
                    (gj, m) => new { Staff = gj.Staff, Training = gj.Training, Manager = m })
              .Where(st => st.Training == null
                        && st.Manager.id == managerId);