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From: r_anderson@banzai.enet.dec.com (Rick Anderson)
Newsgroups: comp.databases
Subject: ORACLE undo/redo logging question
Message-ID: <20897@shlump.nac.dec.com>
Date: 8 Mar 91 14:03:25 GMT
Sender: newsdaemon@shlump.nac.dec.com
Reply-To: r_anderson@banzai.enet.dec.com ()
Distribution: usa
Organization: Digital Equipment Corp.
Lines: 17

ORACLE supposedly supports a record versioning protocol that
allows different read_only users to "see" different versions
of records, depending on when the transaction started.  My 
question is this: Does ORACLE write the record version infor-
mation to the UNDO/REDO log, so that in the case of a failure
not only are the record updates performed, but also the 
previous record versions?

Thanks in advance for any information!
Rick

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* Rick Anderson          * Digital Equipment Corporation *
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