Re: student question: incremental backups (level 0 and level 1)
Date: Thu, 26 Jun 2008 04:57:54 GMT
In article <b42e4167-710f-4071-98a0-ecbfde41d771_at_25g2000hsx.googlegroups.com>, joel garry <joel-garry_at_home.com> wrote:
> On Jun 25, 4:58 am, pellicleund..._at_hotmail.com (obakesan) wrote:
>> >> I would have thought that it is possible for blocks to be used and the=
>> >> free, these blocks should then not need backing up ... no??
>> >> I'd have thought
>> >> it was also possible that eventually (despite being used and freed) th=
>> >> eventually encompas every block in a datafile.
> This does not mean all blocks that *ever* contained data, think of trunca=
>te table for example. So the OP is right to express his doubts about the wo=
>> even if it's not in the sense he originally meant. Another example: drop =
>a table/index/partition and you're likely to to have lots of blocks that on=
well, I tried to be as non-specific as to the mechanism by which a used block might become free or "non-used". The situation of a truncate table (for example) (as I understand it) does not generate undo (once upon a time rollback IIRC) nor (unlike drop table) end up remaining in the tablespace (under a new name).
so perhaps a level 0 is as near as damit a full tablespace copy ... like so many things Oracle I need to ponder this or at least find a description which makes sence to an old programmer (NB new java kiddies see things differently to older folks I've noticed even when we're both talkin OO).
(when bandwidth gets better ;-)
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please remove undies for reply Received on Wed Jun 25 2008 - 23:57:54 CDT