Oracle Backup and Recovery Issue I have backed up database located on Host1 and restored/recovered it on Host2. 
After a while, I backed up DB on Host1 again.

Now I want DBs on Host1 and Host2 be the same using last backup.

How can I achieve this? Without deleting database on Host2?
You should be able to just do a restore/recover over top of the existing Host2.  If you are trying to avoid a complete recovery, then I suspect the answer is you can't, but there are two notable exceptions.


If you never opened the database on Host2 and you have all the archive logs between the first backup and the second, then you can recover Host2 using them.  
If you have opened Host2, you still might be able to do this if you have flashback database enabled and can flash back to the point before you opened it.