RDB DAS provides robust a generic data access service that provides transformation capability between SDO data graphs and relational databases and vise versa.

By using RDB DAS, applications developers 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.

RDB DAS works with SDO to improve your data access performance.The RDB DAS processes the SDO change summary and produces efficient update statements that only write to columns that have actually been modified.

The following diagram illustrates these two capabilities in a typical client interaction.The client starts by reading a graph of data specified by some query.The client then makes modifications to the graph, possibly by adding elements, and then requests the DAS to push the changes back to the database.

To further explore the benefits of DAS please refer to white paper "DAS White Paper: The Data Access Service" on the Documentation page.

Below, there is a list of various links to documents that help to explain various aspects of the Tuscany DAS subproject and the programming model that it provides. More general documentation which applies to the Tuscany project as a whole can be found on the Tuscany Documentation page.

Title	Description
DAS White Paper: The Data Access Service	How to access relational data in terms of Service Data Objects
JDJ DAS Article	How to access relational data in terms of Service Data Objects