Re: student question: incremental backups (level 0 and level 1)

From: obakesan <>
Date: Thu, 26 Jun 2008 04:57:54 GMT
Message-ID: <mlF8k.4034$>


In article <>, joel garry <> wrote:


> On Jun 25, 4:58 am, (obakesan) wrote:
>> >> I would have thought that it is possible for blocks to be used and the=
>n become
>> >> 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=
>is could
>> >> 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).

See Ya
(when bandwidth gets better ;-)

Chris Eastwood
Photographer, Programmer Motorcyclist and dingbat blog:

please remove undies for reply Received on Wed Jun 25 2008 - 23:57:54 CDT

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