Tim, as Kelvin mentioned, DAS would be the component handling heterogeneous data sources, it would be the interface between the Data (SDO Graphs) and the Data repository. From your e-mail, it looks like you want to persist the SDO utilizing Hibernate or Spring DAO. I could see two ways here : Having a new DAS implementation that would utilize this technology to persist the data (but note that Apache have license issues with Hibernate) or refactory DAS to allow plugability of the persistent layer (today RDB DAS uses JDBC under the covers to persist the data to RDB).
Could you also elaborate little more on your cache question ? On Dec 13, 2007 1:39 AM, kelvin goodson <[EMAIL PROTECTED]> wrote: > Hi Tim, > welcome to Tuscany. What I'm not completely clear on from your question > is what you mean by "publish" and "central graph". There's a related > discussion on this list going on (see [1]), and its clear that Jason too had > initial difficulty seeing the picture here until he found the DAS material. > I think perhaps we need to do some work on the SDO part of the Tuscany > website to make this better understood. > > Bert Robben has taken part in that discussion, and his scenario involves > SDO as the primary data API, with conversion to other data formats via an > abstract black box snapshot format being done when necessary, such as > Hibernate being used for some of the back end persistence activity. > > So the notion behind the SDO API design is that in order to access > heterogeneous data sources, Data Access Services will be created to build > SDO data graphs. The RDB DAS is one such example, and you can view the > XMLHelper as providing the services of another. If you are using an RDB as > your central store and want SDO access to the data then the natural solution > is to use the RDB DAS. > > Tuscany has no concept of providing a façade over other data handling > implementations, and I think the disparity in the features of the data > representations you mention would mean that providing an SDO façade would > not be the natural way of solving interoperability. I'd be keen to get a > better idea of your scenario in order to be able to understand in more > detail how SDO can help you. > > Regards, Kelvin. > > [1] http://www.mail-archive.com/tuscany-user@ws.apache.org/msg02162.html > > > On 13/12/2007, Tim Frey <[EMAIL PROTECTED]> wrote: > > > > Hello, > > > > > > > > I searched the whole day how i could build up a data graph and publish it > > via SDO. > > > > I want to access the data graph via Tuscany SDO. > > > > I found out about the relational solution DAS, but I would like to have > > the > > data graph as Java objects with hibernate persistency. Or Maybe even > > better > > have also spring DAOs as nodes in the graph. > > > > How can I build up a central graph and is this even possible to do what I > > want? > > > > Or is the relational solution also capable of caching? > > > > > > > > Sorry maybe this questions are answered somewhere but I don't find out > > where > > to start. > > > > I really hope that someone can help that I can build up a central data > > store > > accessed in a unified way in my application. > > > > Or maybe someone can propose me a better solution than SDO for that. > > > > > > > > Kind regards > > > > Tim Frey > > > > > -- Luciano Resende Apache Tuscany Committer http://people.apache.org/~lresende http://lresende.blogspot.com/ --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
