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From Mike Matrigali <mikem_...@sbcglobal.net>
Subject Re: Derby-573 - optimizer overrides changes to metadata.properties and upgrade
Date Fri, 11 Nov 2005 18:59:51 GMT
I am not sure if there is a place - maybe dan has written something up.

The way I think about it is, if your 10.2 feature can not work without
db upgrades to a 10.1 db it should be disabled in soft upgrade.  If
your feature would somehow change the 10.1 db such that 10.1 server
will no longer work in some way then it must be disabled in soft

The one I am never sure about is I believe it ok to add a feature
available under soft upgrade, even it an application which uses it will
no longer work under the previous version, since in that case the
application decided to make itself not backward compatible.

Mamta Satoor wrote:
> I will have to admit my ignorance on soft upgrade. Can you point me 
> somewhere to understand what is involved in a soft upgrade and then I 
> will be able to answer your question?
> Mamta
> On 11/11/05, *Mike Matrigali* <mikem_app@sbcglobal.net 
> <mailto:mikem_app@sbcglobal.net>> wrote:
>     In the case of soft upgrade (ie. the case where there are no changes
>     to the metadata.properties) will you be disabling the new optimizer
>     overrides?
>     Mamta Satoor wrote:
>      > Hi,
>      >
>      > The patch for optimizer overrides includes changes in
>      > metadata.properties. I think this change in metadata.properties
>     is going
>      > to require some form of upgrade code so that the sql text stored
>     in the
>      > systems tables can be replaced with new sql text which uses this new
>      > form of optimizer overrides.
>      >
>      > I wondered if anyone can give me some pointers on how to get started
>      > with upgrade code to achieve this. In the mean time, I will start
>      > looking into it too.
>      >
>      > thanks,
>      > Mamta

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