postgresql7.1
select s2.object_id as subsite_id, tree_level(s2.tree_sortkey) as level
from site_nodes s1, site_nodes s2, apm_packages p
where s1.node_id = :node_id
and s2.tree_sortkey <= s1.tree_sortkey
and s1.tree_sortkey like (s2.tree_sortkey || '%')
and p.package_id = s2.object_id and p.package_key = 'acs-subsite'
order by level
limit 1