Thanks Uwe for the link. It is indeed what i was looking for.
Is there any document that lists 'Optimizer (CBO) enhancements' in 18.104.22.168 ?
I have ~200 prod dbs running on 22.214.171.124 (both, OLTP and DW) and i need to upgrade them to 126.96.36.199 in next month. It would be good to see 188.8.131.52 new features/bug fixes on optimization front !