opatch is used to see applied patches at database level.
What command or how to check what are patches have been applied to Oracle E-Business Suite?
1. MetaLink Note:162498.1
or
2. By querying the database:
SELECT bug_number FROM ad_bugs WHERE bug_number IN ('patch_number', 'patch_number', . . .) ORDER BY bug_number DESC;
-- //www.freelists.org/webpage/oracle-l