[Zope] ZODB drops _v_ attributes.

Etienne Labuschagne elabuschagne@gmsonline.co.za
Tue, 08 Apr 2003 15:03:47 +0200


Just a question in general on this subject:

When I retrieve an object out of a ZODB and that object instantiates some 
volatile variables.  How long can I expect that object to hang on to those 
volatile variables?

Shouldn't they last at least until I let go of my reference to the object?

Thanks
Etienne

At 01:48 PM 4/8/2003 +0100, Toby Dickenson wrote:
>On Tuesday 08 April 2003 1:27 pm, ZOPE Developer wrote:
> > Hi.
> >
> > I use the standalone ZODB.
> >
> > When I create persistent objects containing _v_ (volatile
> > attributes), and access them at an extremely high
> > rate(reading and using), they sometimes lose their _v_
> > attibutes.
>
>Thats what volatile means!
>
> > Can somebody tell me what I need to do the avoid this?
>
>To stop the attribute value disappearing? Make it non-volatile.
>
>To detect the situation and avoid the AttributeError? Use hasattr, or set a
>shadow class attribute with a null value.
>
>--
>Toby Dickenson
>http://www.geminidataloggers.com/people/tdickenson
>
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