The Microsoft.ReportingServices.DataProcessing namespace is modeled after a subset of the Microsoft .NET data provider interfaces. These interfaces contain the minimal subset of the .NET data provider functionality needed by the report server to process custom data, and do not reflect a fully implemented .NET data provider. You do not need to create a new data processing extension for Reporting Services, if an existing data provider already implements the data processing extension interfaces. As in the case of a .NET data provider, a Reporting Services data processing extension enables you to connect to a data source in order to retrieve data.
Provides a means of reading one or more forward-only streams of result sets obtained by executing a command at a data source, and is implemented by Reporting Services Data Processing Extensions that access relational databases.
Provides a means of reading one or more forward-only streams of result sets obtained by executing a command at a data source, and is used by SQL Server Reporting Services to retrieve aggregation-specific information about a result set.