I just started to do some backup/recovery testing. I used the same one channel and all backup sets went to the same directory. It seems that Oracle select the most recent backup by default when do recovery. My question is: How can I use the old backup which is not the most recent backup to do recovery?

Another question is, usually how many channels do people use for regular backup activities like weekly entire database backup and full tablespace backup, daily incremental tablespace backup, etc ?

Thanks for any help.