title: Linq query with nested select(s)
body: <p>Trying to figure out the right way to express the following SQL in a linq statement and getting nowhere.</p>
  
  <pre><code>select messageid, comment 
  from Message 
  where isactive = 1 and messageid in 
  (
      select messageid 
      from org.Notification 
      where NotificationTypeId = 7 and orguserid in 
      (
          select OrgUserId 
          from org.OrgUser
          where OrgId in 
          (
              select ChildOrgId from OrgRelation
              where ParentOrgId = 10001
          )
      )
      group by messageid
  )
  </code></pre>
  
  <p>This works as-is in SQL Server, but I want to use this query in C# (E-F) code, and I seem to be running around in circles.</p>