On our server (exadata) this select executes about 10 minutes.
Fix it by this please:
SELECT t.*, o.*, m.comments
from sys.all_tables t,
sys.all_tab_comments m,
sys.all_objects o
where t.owner = :object_owner
and t.table_name = :object_name
and m.owner (+) = t.owner
and m.table_name...