LINQ left self join

Asked May 07 '15 at 13:21

Active May 07 '15 at 13:21

Viewed 342 times

I have LINQ query as below:

lst_direct_managers = context.sf_guard_user_profile
 .Join(context.sf_guard_user_profile, up => up.user_id, dm => dm.direct_manager_id,
 (up, dm) => new { up, dm })
 .Where(m => m.up.is_gvo == 1)
 .Select(m => new DirectManagerModel
  {
  user_id = m.up.direct_manager_id == null ? 0 : m.up.direct_manager_id,
  dm_full_name = (m.up.first_name + " " + m.up.last_name == null ? "No Direct Manager" : m.up.first_name + " " + m.up.last_name)
  })
  .Distinct()
  .OrderBy(m => m.dm_full_name).ToList();

Problem is that it does not return default value in case of nulls "No Direct Manager". Can you please help me?

asked May 07 '15 at 13:21

ironcurtain

2

What you are doing is Inner join not left join. – Jenish Rabadiya May 07 '15 at 13:24
m.up.first_name + " " + m.up.last_name: would this ever equal null? – Matthew North May 07 '15 at 13:25
@MatthewNorth only direct_manager_id can be null. – ironcurtain May 07 '15 at 13:28
@ironcurtain visit [How to implement left join in JOIN Extension method](http://stackoverflow.com/a/3792904/1505865) – Jenish Rabadiya May 07 '15 at 13:29
It's this line: dm_full_name = (m.up.first_name + " " + m.up.last_name == null ? "No Direct Manager" : m.up.first_name + " " + m.up.last_name) I was asking about, it looks like it would throw an exception instead of returning 'No Direct Manager' – Matthew North May 07 '15 at 13:40
Use a navigation property in stead of a join. – Gert Arnold May 07 '15 at 13:55

LINQ left self join

0 Answers0