[elephant-devel] Safe to change definition of a persistent class?
Ben
ben at medianstrip.net
Mon Jan 17 01:07:27 UTC 2005
Adding and removing slots should be safe. There is 1 entry per slot
per instance. Non-existent entries are the same as "unbound slots."
So adding a new slot will make existing instances have unbound slots.
Removing a slot doesn't do anything, it just leaves cruft in the DB.
There are certain rules about changing a slot from transient to
persistent and vice versa -- I think they're laid out in the tutorial.
take care, B
On Mon, 17 Jan 2005, Stefan Scholl wrote:
> Hi!
>
> Is it safe to change the definition of a persistant class which already had
> some serialized instances at some other time?
>
> Given some objects got written to the store and you change the class in the
> further development process (reevaluation defclass, rereading changed source,
> etc.) of your project. Will the data be crippled? Just right by coincidence?
> Or no problem at all (as long as you just add or remove slots)?
>
>
> Regards,
> Stefan
>
>
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