Hi there,
I've a question for my personal understanding. I've read pretty much everywhere that a backup must be taken AFTER a NOLOGGING operation. If I want to make a risky operation, I would intuitively make a backup BEFORE doing it... Can anyone shed the light on WHY the backup should be taken before the NOLOGGING operation ? What happens if I don't do a backup even if everything went fine ? Would my database (or the objects involved in the nologging operation) be corrupted somehow at some point, and if so, when and why ?
Extra question: I know that if the database is shut down after the operation or if there is a crash in between, the data that were generated / modified won't be accessible anymore. Let aside the fact that I don' understand why taking a backup would fix this, suppose that the operation was targeting a simple table. Would the corruption issue only concern the table itself, or could it potentially concern the whole data file or tablespace ?
Thanks in advance for your help