MySQL nested set non-children relationships

Question

I have a nested set of organisations, that looks something like this (the nodes are org ids):

1234 is a parent of 4499 and 3322, but 9905 is "affiliated", not really a parent or child, to 1234.

I believe that the leftedge, rightedge set up should look something like:

orgID | leftedge | rightedge
1234  |   1      |    6
4499  |   2      |    3
3322  |   4      |    5
9905  |   7      |    8

Since 9905 isn't really a Child of 1234, i'm not sure how i can get the relationship between 1234 and 9905. The SQL i use to get child relationships is:

SELECT ost.orgid, ost.leftedge, ost.rightedge
  FROM tbl_organisationsettree ost 
  JOIN tbl_organisationsettree AS child_ost ON child_ost.leftedge BETWEEN ost.leftedge AND ost.rightedge 
   AND child_ost.supersetid = ost.supersetid 
 WHERE 1 
   AND ost.leftedge > 1 
   AND ost.rightedge <6 
GROUP BY child_ost.ID 
HAVING COUNT(child_ost.ID) = 1

Answer 1

Finds any node that is not descedant or ancestor of node 1234:

SELECT ost.*     --- whatever from `org` table
FROM tbl_organisationsettree AS ost 
   JOIN tbl_organisationsettree AS param
      ON  param.leftedge NOT BETWEEN ost.leftedge 
                                 AND ost.rightedge
      AND ost.leftedge NOT BETWEEN param.leftedge 
                               AND param.rightedge
WHERE param.orgID = 1234 

--- if you only root nodes:
---
--- AND NOT EXISTS 
---     ( SELECT *
---       FROM tbl_organisationsettree AS parent
---       WHERE ost.leftedge > parent.leftedge 
---         AND ost.leftedge < parent.rightedge
---     )
;