Well, the accessing sql is refreshingly simple, but the updating code 
BEGIN
DECLARE right_most_sibling INTEGER;

SET right_most_sibling
    = (SELECT rgt
         FROM Personnel
        WHERE emp = :your_boss);

UPDATE Personnel
   SET lft = CASE WHEN lft > right_most_sibling
                  THEN lft + 2
                  ELSE lft END,
       rgt = CASE WHEN rgt >= right_most_sibling
                  THEN rgt + 2
                  ELSE rgt END
 WHERE rgt >= right_most_sibling;

INSERT INTO Personnel (emp, lft, rgt)
VALUES ('New Guy', right_most_sibling,
                  (right_most_sibling + 1))
END;

[download]
Is rather scary and I'm not even sure my database (mysql) supports those.

In reply to Re: Re^3: (OT?) Recursive sql queries? by BUU
in thread (OT?) Recursive sql queries? by BUU

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