persistence@glassfish.java.net

Re: Caching-Between-Transactions

From: Adam Bien <abien_at_adam-bien.com>
Date: Tue, 15 Aug 2006 10:41:15 +0200

Hi Marina,


Marina Vatkina schrieb:
> Hi Adam,
>
> Are you asking about CMP or Java Persistence implementation?
> They are based on 2 different code bases in glassfish ('cmp'
> and 'entity-persistence' sub-modules).
>
> CMP supports version consistency, and as such "caching between
> transactions" for those beans that choose to use this consistency
> level. It also supports read-only CMPs which states are cached for a
> period of time (refresh interval).
>
> JPA implementation always uses "caching between transactions",
> and you need to call an explicit refresh, to reload an instance
> from a database (like you have by default in CMP).
>
Really, I would expect, that in every new transaction I would get fresh
data from database?
Thanks,

adam
> HTH.
>
> Regards,
> -marina
>
> Adam Bien wrote On 08/14/06 08:11,:
>
>> I read the following thread:
>> http://www.theserverside.com/news/thread.tss?thread_id=41748
>>
>> Do glassfish not support the notion of "caching between transactions"
>> or commit-option A (from CMP 2.1)?
>>
>> This is important for real world...
>>
>> regards,
>>
>> adam
>>
>>
>>
>
>


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