Re: About undo blocks & read consistency

From: Paul Brewer <paul_at_paul.brewers.org.uk>
Date: Wed, 9 Jul 2003 20:27:45 +0100
Message-ID: <3f0db42c_2@mk-nntp-1.news.uk.worldonline.com>

"Spendius" <spendius_at_muchomail.com> wrote in message news:aba30b75.0307090351.17aaff81_at_posting.google.com...
> About undo blocks & read consistency
>

<snip>

Simplistic explanation, but it might help:

Oracle will always write the undo (and the redo for the undo) *first*.

So it will always give you a read consistent image (unless it can't, because of 1555, in which case you are still safe, because it will refuse to give you an image at all).

Don't worry about what is happening with the data block. It will take care of itself in its own good time.

Regards,
Paul Received on Wed Jul 09 2003 - 14:27:45 CDT