Datafile Lost due to OS level delete:
Recovery of a Missing Datafile that has no backups (database is open).
If a non system datafile that was not backed up since the last backup is missing,
recovery can be performed if all archived logs since the creation
of the missing datafile exist.
Pre requisites: All relevant archived logs.
1. alter datafile offline immediate;
2. alter database create datafile ‘fully_qualified_file_name’;
3. alter database datafile ‘fully_qualified_file_name’ online;
If the create datafile command needs to be executed to place the datafile on a
location different than the original use:
alter database create datafile ‘fully_qualified_file_name’ as ‘fully_qualified_file_name’;