Service Data Objects (SDOs) have become a foundation technology for Service Oriented Architecture (SOA). Recently, BEA, IBM, Oracle, SAP, Iona, Siebel, and Sybase announced their support for an SOA-enabling framework specification named Service Component Architecture (SCA). SD O provides the primary data representation in this framework.
What SDO/DAS can do for you ?
Although not addressed by the current SDO or SCA specifications, there's a definite need for a generic data access service that operates in terms of SDOs. The alternative to this service would be the tedious and error-prone development of a custom mapping between the back-end data representation and Service Data Objects.
The Relational Database Data Access Service (RDB DAS) obviates the need for this custom development by providing a robust data access utility built around SDO. Because of its tight integration with SDO, the RDB DAS is also a perfect solution for data access in an SCA-based application.
By employing the RDB DAS, applications avoid the details and complications of working directly with a relational database and also the complex transformation between relational rows/columns and Data Object types/properties.
Today, Tuscany C++ SDO work in conjunction with SDOHelper to map back-end data representation to Service Data Objects. There is a need for a C++ DAS implementation that would interop with the C++ SDO and mediate between the SDO and the back-end store.
Currently, Tuscany DAS only support RDB back-ends, altough the idea is that DAS could access and mediate data trough various backends representations, XML being one of them. This project consists in designing the DAS implementation over XML, how the commands would be structured (e.g using XQuery, XPath, etc) and also contribute important feedback to a possible DAS spec.
DAS and non-SDO data types
Currently, Tuscany DAS only generate static or dynamic Service Data Objects. This project consist in generating different object types as a result of a DAS command. This project would include extending DAS to understand what types should be generated, investigating and solving problems like how to handle change summaries, etc.This could be applied not only for the current DAS RDB implementation, but in conjunction with other implementations like XML DAS.
DAS implementation type