Hi Phil,
the general question you raise is rather difficult to answer. The best
technology decision depends on many aspects and I think one would have
to know your use case very precisly to make a good choice. There also
some organizational aspects involved in your question, e.g. how active a
certain project is. I will try to answer the detailed questions, if you
need more help with the general decision, feel free to contact me via mail.

Am 15.11.2013 14:35, schrieb Phil Wim:
> Hi there,
>
> I am working on an application, which needs so manage Ecore Data as the
> applications master data and create, in a second layer, many many
> instances of the EMF nodes. For the first part of managing master data,
> I'm using ECP and EMFStore. It brings everything I need in a quick pace.
> Editing master data is possible by just using my Ecore with ECP.
> EMFStore brings the functionality for save working in master data.
>
> On the second layer, I want a dynamic creation of master-data-node
> instances and persisting them. My understanding of EMFStore persistency
> is based on XMI (which is a XML). The goal is to store unlimited
> instances without losing performance. For not running in "Out of
> memory", I need a database-based approach, I guess? In addition, I need
> a Query Language (Select, Aggregating sum count etc.) for searching and
> aggregating instances.
>
> Therefore, my idea was to set up a hybrid environment, where EMF and ECP
> are responsible for master data and CDO for instances and searching them.
>
> Now I come to a point where I want to rely on a more progressive
> experience then mine. I am happy about any contribution!
>
> My Questions:
>
> 1) Is my depicted approach the right one?
Hard to answer without understanding your use case more in detail
>
> 2) Is CDO the right choice for storing massive data and being able to
> query the instances? Or is EMFStore still the right choice?
CDO offers more scalability options than EMFStore does. Especially the
weak references might be interesting for you if the data you store is
connected. This allows lazy loading and garbage collection of objects.
CDO supports several backends, mostly databases. CDO has an own query
language.

EMFStore has also an exchangable backend, only the default is XMI. It is
also possible to store EMFStore data into a database or even into a CDO
repository.
>
> 3) Is EMFStore also able to query huge amount of data?
EMFStore currently does not provide a query mechanism itself.
>
> 4) What about the projects:
> - mongo-emf (github.com/BryanHunt/mongo-emf/wiki/User-Guide) and EMF
> Teneo Model: Database approach with Query Language? Any experience with
> it? Is it suitable for my concerns?
Depending on your requirements, but of course it is possible to
implement persistence qithout EMFStore or CDO.

> - IncQuery: I just read that there will be a prototype implementation
> with EMF Store
> (http://www.eclipse.org/forums/index.php/mv/msg/404512/958921/#msg_958921)
IncQuery is independat of EMFStore or CDO, should be easy to fully
integrate it.
> - EMFQuery? Still alive?
Hmm, probbaly not.

Last but not least, I would like to mention, that you can use ECP with
other backends, such as CDO or even a custom solution..
Regards

Jonas

>
> Thanks in advanced
>
> Cheers Philippe
>