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From Daniel John Debrunner <...@debrunners.com>
Subject Re: Migration from to 10.1
Date Mon, 01 Aug 2005 16:46:46 GMT
Øystein Grøvlen wrote:

>>>>>>"DJD" == Daniel John Debrunner <djd@debrunners.com> writes:
>     DJD> Fully functioning engine in soft upgrade mode, except for the new
>     DJD> features that would leave persistent data that would not be understood
>     DJD> by an older release. For 10.1 that would be SYNONYMS etc.
>     DJD> Ie. multi-user, read/write. The intention is that applications can try
>     DJD> out the new engine version with no changes and see if it fixes bugs or
>     DJD> improves (or degrades) performance.
> Is there any performance impact of doing soft-upgrade? That is, does
> it imply data conversion from/to old data format, or is this avoided
> by making the class loading dependent on the data format?

That can only be answered when someone makes changes that modify the a
stored format and uses the old format in soft upgrade mode and the new
format after full upgrade.

The current soft upgrade restrictions just disable SQL features that
would not be handled by the old release, e.g. SYNONYMS would leave
entries in SYSALIASES that might cause problems for 10.0.


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