[ZODB-Dev] Serializability

[Jim Fulton]

On Aug 21, 2007, at 1:55 PM, Dieter Maurer wrote:

> Jim Fulton wrote at 2007-8-20 10:32 -0400:
>> ...
>>> Application specific conflict resolution
>>> would become a really difficult task.
>>
>> I'm sure you realize that application specific conflict resolution
>> violates serializability.
>
> No, I do not realize this.
>
> Assume a counter which is not read only incremented/decremented.
> Its "application specific conflict resolution" ensures
> that the schedule is serializable restricted to the counter value.
>
> Things are much more complex when the counter is read (and  
> incremented).
> Usually, serializability is lost, then.

I should have been more precise.  When application-level conflict  
resolution is used, then the database is no-longer providing  
serializability.  It is up to the application to do so (or to provide  
"correctness" in some other way.

Jim

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