The Microsoft.SharePoint.Dsp namespace provides the base class for the data retrieval service adapters used in Microsoft Windows SharePoint Services. The adapters define a protocol for data consumers to query heterogeneous data sources and for the data sources to return query results back to the consumers, integrating different types of data into a unified format so that they can be related, analyzed, and manipulated easily.
Each data retrieval service provides a data-binding scheme that enables data consumers and data servers to communicate with each other through Simple Object Access Protocol (SOAP) or the object model of Windows SharePoint Services. The client side of the data retrieval services consists of data consumers such as applications, data-driven Web Parts, or data-bound server controls. The server side of the data retrieval services is a group of adapters, which are Web services that return XML data from different data sources or that perform data-manipulation operations in those data sources. The following adapters are used in Windows SharePoint Services:
The Microsoft.SharePoint.Dsp.Sts namespace has both an object model and a SOAP interface, while the other three namespaces have only an object model.
The adapters provide an object model that can be used by other Microsoft .NET managed assemblies. Server components can load the assembly of a service directly, eliminating the overhead of calling the service through SOAP. All adapters implement the IDspAdapter interface of the Microsoft.SharePoint.Dsp namespace, and by dynamically loading the data retrieval service assemblies, the same client code can be written to talk to any of the adapters.
The following table lists the classes of the Microsoft.SharePoint.Dsp namespace and provides a brief description of each.
|AllFields||Used in a query to specify that all the fields be returned from the data source.|
|Authentication||Represents the authentication mode that is used to connect to the back-end server.|
|Connection||Represents a connection to a data retrieval service adapter.|
|DataRoot||Represents the root of the content document for a particular adapter instance.|
|DspQuery||Defines the filter used in a query against a data source provider.|
|DSQuery||Represents a query used by a data retrieval service.|
|Field||Represents a single column in a query.|
|Fields||Represents the collection of columns that are included in a query.|
|OrderField||Represents the column by which the result is ordered.|
|PTQuery||Represents a pass-through query.|
|QueryRequest||Represents the request in a query.|
|QueryResponse||Represents the response in a query.|
|Request||Represents the request header in a query, containing information about the operation type and the document type of the query.|
|RequestHeader||Represents the request header in a query.|
|Response||Represents the response in a query.|
|ServerParameter||Represents a server parameter required by the server containing the data source.|
|ServerParameterInfo||Represents information about the parameters used by the server containing the data source.|
|Versions||Represents the versions of the data retrieval service that are supported by an adapter or the versions being used in a query.|
The following table lists the enumerations of the Microsoft.SharePoint.Dsp namespace and provides a brief description of each.
|ColumnMappingType||Indicates the type of XML format used for data returned in a query.|
|DocumentType||Specifies the document type for a request.|
|MethodType||Specifies the action of the request.|
|OrderDirection||Specifies the direction in which a field or column is sorted.|
|PagingSupportType||Indicates the type of paging that is supported for a query.|
|ResponseStatus||Specifies the status of a query response.|
|ResultContentType||Indicates the type of content that is returned through a query.|
The following table lists the interfaces of the Microsoft.SharePoint.Dsp namespace and provides a brief description of each.
|IDspAdapter||Provides a COM interface for clients to access a data retrieval service adapter locally.|