postgresql7.2
select object_id,name, name as rawname, 1 as level from site_nodes s where s.parent_id is null;
select n.name,
n.object_id,
n.name as rawname,
tree_level(n2.tree_sortkey) as level
from site_nodes n, site_nodes n2
where n.name is not null
and n.tree_sortkey between n2.tree_sortkey and tree_right(n2.tree_sortkey)
and n.object_id in (select s.object_id from site_nodes s where s.parent_id is null)