Hi All I have just read through http://www.oracle.com/technetwork/database/features/availability/edition-based-redefinition-1-133045.pdf This looks damn interesting! But am thinking if at all anyone used this feature...if so any inputs on this? P.S==>I want to explore this option to use for oracle DB upgrades and Oracle Ebiz applications...i know it would be very long journey but my thoughts are like how best we can use this feature..:-),neverthless its a never ending thirst of zero downtime with less investment..:-) too many gotcha's... thanks, Edwin.K -- //www.freelists.org/webpage/oracle-l