On 8/15/06, Adam Bien <abien_at_adam-bien.com> wrote:
>
> 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?
I don't think so. Even in a transaction-scoped persistence context, TopLink
caches entities in the sesion cache so if you do em.find() you will get
cached result. You can call em.refresh() after em.find() or execute query
with query hint "toplink.refresh" to get fresh one from database.
- Wonseok
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
> >>
> >>
> >>
> >
> >
>
>
> --
> Dipl. Inf. adam bien
>
> BEA Technical Director
> Sun Certified Java Programmer
> Sun Certified Enterprise Java Architect
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>
> Mobile: 0049(0)170 280 3144
> eMail: abien_at_adam-bien.com
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> ----------
> Book author:
>
> Enterprise Architekturen
> entwickler.press 2006
> ISBN: 393504299X
>
> and Enterprise Java Frameworks,
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>
>
--
Wonseok Kim
Senior Developer, TmaxSoft