I just realized that you may not be able to access the site-map via the browser. So you can try:
select * from acs_permissions where object_id = (select object_id from site_nodes where parent_id is null)
I guess you could also add this clause since your main site surely inherits from the 'default context':
union select * from acs_permissions where object_id = acs__magic_object_id('default_context')
G'luck...
