At  05:46 PM 5/16/01, John MacLerran wrote:
>Question about TurboStore with the Online option enabled. What happens to
>Image databases that are in use, but can't be quiesced properly (e.g.
>because DBXBegin and DBXEnd wasn't used)?
>
>Are they skipped, or are they still backed up?  (I realize that, depending
>on the processing being done, they could be physically fine, but logically
>inconsistent; I'm just trying to understand how TurboStore handles the
>situation.)

See: http://docs.hp.com/mpeix/onlinedocs/B5151-90003/00/00/43-con.html

My understanding is that TurboStore's online mechanism provides the same
degree of protection to logical, physical and system transactions as MPE/iX
(with transaction-manager, but *withOUT* image logging and roll-forward or
roll-back recovery) provides across a system failure and restart.  In other
words, if you aren't using DBXBEGIN/DBXEND to ensure that your transaction
is completed or rolled back, then Image considers each Image intrinsic call
a standalone transaction.

In other words, TurboStore-Online & Image (without DBXBEGIN) reduces
"logical integrity" to match "physical integrity".

The only thing I don't recall clearly, is whether DBBEGIN/DBEND provide
comparable protection to logical integrity during online backups that they
provide with logging recovery.

-- Jeff Woods

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