If it is required that the data loaded using the NOLOGGING option needs to be recovered in the case of a disaster situation, your only solution is making a backup as soon as the NOLOGGING operation is made. Otherwise, the data cannot be recovered in the event of a media failure because it has not been logged.
Sometimes you will not be able to run a full backup of the database until later in the day. In this situation, you can make use of the following strategies:
Hot backup
In order to recover any additional data or modification to the table after the bulk insert using
NOLOGGINGis complete, you must at least perform a hot backup of the datafiles in which the objects are located. Remember that your database continues generating redo for the DML transactions over the objects, even if they are still using theNOLOGGINGoption, but you are strongly advised to place them inLOGGINGafter theNOLOGGINGmode is no longer required, to avoid any possibility of unrecoverability...