Re: What *really* happens at ALTER TBSP END BKP ?

"Quarkman" <quarkman_at_nowhere> wrote in message news:<3f0487c4$0$730$afc38c87_at_news.optusnet.com.au>...
>
> In particular, END BACKUP does *not* cause a checkpoint to be issued, and
> does not therefore bring the SCN of the tablespace back into synchronisation
> with the SCN in the headers of all other datafiles. Many books reckon you
> should issue an 'alter system switch logfile' or similar just after the END
> BACKUP command, because only then are the various SCNs synchronised, because
> of the system-wide checkpoint that command causes. But there's really not a
> lot of point, since if you just wait long enough, another checkpoint will
> take place naturally anyway. (It is true, however, that until the headers
> are synchronised, you are a little vulnerable to an unexpected instance
> failure... Oracle would demand you perform a media recovery on subsequent
> startup to correct the SCN mismatch, when in fact no real media recovery is
> required). Assuming you don't suffer from instance failures on a regular
> basis, however, the extra checkpoint those books recommend is a bit
> unnecessary.

...horrible visions of someone doing a shutdown abort just after the backup... then handing it off to me to recover with no explanation of what is going on...

jg

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