Whenever we perform incomplete recovery or recovery with a backup control file, you must reset the online logs when you open the database. The new version of the reset database is called a new incarnation.
 

Action performed while opening database base with RESETLOGS options

1.Archives the current online redo logs (if they are accessible) and then erases the contents of the online redo logs and resets the log sequence number to 1. For example, if the current online redo logs are sequence 1000 and 1001 when you open RESETLOGS, then the database archives logs 1000 and 1001 and then resets the online logs to sequence 1 and 2.

2.Creates the online redo log files if they do not currently exist.

3.Reinitializes the control file metadata about online redo logs and redo threads.

4.Updates all current datafiles and online redo logs and all subsequent archived redo logs with a new RESETLOGS SCN and time stamp.

Because the database will not apply an archived log to a datafile unless the RESETLOGS SCN and time stamps match, the RESETLOGS prevents you from corrupting datafiles with archived logs that are not from direct parent incarnations of the current incarnation.