Hi Martin > But I'm very interrested if the cache changes anything, especially > if it's different in manual or AMM configuration. What I found in this area is published at the end of page 178 (Formula 5-3) in my book. Cheers, Chris PS: you can preview the book through Google Book Search (http://books.google.com/books?id=w8qzDTUVHSQC&printsec=frontcover#PPP1,M2) -- //www.freelists.org/webpage/oracle-l