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From Jörg von Frantzius <joerg.von.frantz...@artnology.com>
Subject Re: Feature proposal for JDO 2.1 maintenance: current DB time
Date Thu, 19 Oct 2006 08:33:24 GMT
Hello Craig,

as far as I can see that does satisfy our requirements. Once we are able 
to query for that date in JDOQL, we can use it e.g. for lastmodification 
timestamps and the like.

Regards,
Jörg

Craig L Russell schrieb:
> It's easy enough to define "new Date()" as being evaluated on the back 
> end for queries that are executed on the back end. And being evaluated 
> in the vm for queries that have a bound candidateCollection.
>
> But does this satisfy the requirements? Once you have a Date in JDOQL, 
> what can you do with it?
>
> Craig
>
> On Oct 16, 2006, at 11:58 AM, Erik Bengtson wrote:
>
>> +1. maybe "new Date()" could be the expression where evaluation 
>> occurs on the
>> database.
>>
>> Quoting Jörg von Frantzius <joerg.von.frantzius@artnology.com>:
>>
>>> Dear experts,
>>>
>>> there had been several occasions where in our applications we had to
>>> determine the database server's current time(-stamp). In one 
>>> application
>>> we needed it to synchronize sent JMS messages with visibility of 
>>> commits
>>> in the database, and in another we need it for our simple replication
>>> algorithm.
>>>
>>> In distributed systems in general it is often crucial for
>>> synchronization purposes to have a common source of time information
>>> that is accessible from all processes.
>>>
>>> It would be great if JDO2 could offer a way of doing that independently
>>> of the database, e.g. as a JDOQL function.
>>>
>>>
>>> Regards,
>>> Jörg
>>>
>>
>>
>>
>
> Craig Russell
> Architect, Sun Java Enterprise System http://java.sun.com/products/jdo
> 408 276-5638 mailto:Craig.Russell@sun.com
> P.S. A good JDO? O, Gasp!
>


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