Re: Rollback extents

"Rene Nyffenegger" <rene.nyffenegger_at_gmx.ch> wrote in message news:Xns923BCFECF86gnuegischgnueg_at_130.133.1.4...
>
> > And also the original poster seems to imagine that rollback io is done
> > on a per row changed rather than a per block changed basis.
>
> And if it was not the OP that imagined so, at least I did. Well, again
> something where I was wrong in my thinking about how Oracle internally
> handles things.
>
> Does your answer imply that oracle used a full redo block as soon as a
> transaction changes only a byte on a db block, but never uses more than
> one redo block for every block on which a byte is changed.
>
> Could you give me a pointer where I find more about this things. I find
them
> extremly exciting.
>
> Rene

All Oracle IO is done in units of blocks. so rollback segments contain blocks of data just as other segments do.

Rollback segments are discussed at
http://otn.oracle.com/docs/products/oracle8i/doc_library/817_doc/server.817/ a76965/c02block.htm#8401

--
Niall Litchfield
Oracle DBA
Audit Commission UK
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